Fix Proxy Protocol v2 handling
[exim.git] / src / src / expand.c
CommitLineData
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1/*************************************************
2* Exim - an Internet mail transport agent *
3*************************************************/
4
bc338899 5/* Copyright (c) University of Cambridge 1995 - 2013 */
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6/* See the file NOTICE for conditions of use and distribution. */
7
8
9/* Functions for handling string expansion. */
10
11
12#include "exim.h"
13
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14/* Recursively called function */
15
b0e85a8f 16static uschar *expand_string_internal(uschar *, BOOL, uschar **, BOOL, BOOL, BOOL *);
96c065cb 17
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18#ifdef STAND_ALONE
19#ifndef SUPPORT_CRYPTEQ
20#define SUPPORT_CRYPTEQ
21#endif
22#endif
23
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24#ifdef LOOKUP_LDAP
25#include "lookups/ldap.h"
26#endif
27
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28#ifdef SUPPORT_CRYPTEQ
29#ifdef CRYPT_H
30#include <crypt.h>
31#endif
32#ifndef HAVE_CRYPT16
33extern char* crypt16(char*, char*);
34#endif
35#endif
36
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37/* The handling of crypt16() is a mess. I will record below the analysis of the
38mess that was sent to me. We decided, however, to make changing this very low
39priority, because in practice people are moving away from the crypt()
40algorithms nowadays, so it doesn't seem worth it.
41
42<quote>
43There is an algorithm named "crypt16" in Ultrix and Tru64. It crypts
44the first 8 characters of the password using a 20-round version of crypt
45(standard crypt does 25 rounds). It then crypts the next 8 characters,
46or an empty block if the password is less than 9 characters, using a
4720-round version of crypt and the same salt as was used for the first
48block. Charaters after the first 16 are ignored. It always generates
49a 16-byte hash, which is expressed together with the salt as a string
50of 24 base 64 digits. Here are some links to peruse:
51
52 http://cvs.pld.org.pl/pam/pamcrypt/crypt16.c?rev=1.2
53 http://seclists.org/bugtraq/1999/Mar/0076.html
54
55There's a different algorithm named "bigcrypt" in HP-UX, Digital Unix,
56and OSF/1. This is the same as the standard crypt if given a password
57of 8 characters or less. If given more, it first does the same as crypt
58using the first 8 characters, then crypts the next 8 (the 9th to 16th)
59using as salt the first two base 64 digits from the first hash block.
60If the password is more than 16 characters then it crypts the 17th to 24th
61characters using as salt the first two base 64 digits from the second hash
62block. And so on: I've seen references to it cutting off the password at
6340 characters (5 blocks), 80 (10 blocks), or 128 (16 blocks). Some links:
64
65 http://cvs.pld.org.pl/pam/pamcrypt/bigcrypt.c?rev=1.2
66 http://seclists.org/bugtraq/1999/Mar/0109.html
67 http://h30097.www3.hp.com/docs/base_doc/DOCUMENTATION/HTML/AA-Q0R2D-
68 TET1_html/sec.c222.html#no_id_208
69
70Exim has something it calls "crypt16". It will either use a native
71crypt16 or its own implementation. A native crypt16 will presumably
72be the one that I called "crypt16" above. The internal "crypt16"
73function, however, is a two-block-maximum implementation of what I called
74"bigcrypt". The documentation matches the internal code.
75
76I suspect that whoever did the "crypt16" stuff for Exim didn't realise
77that crypt16 and bigcrypt were different things.
78
79Exim uses the LDAP-style scheme identifier "{crypt16}" to refer
80to whatever it is using under that name. This unfortunately sets a
81precedent for using "{crypt16}" to identify two incompatible algorithms
82whose output can't be distinguished. With "{crypt16}" thus rendered
83ambiguous, I suggest you deprecate it and invent two new identifiers
84for the two algorithms.
85
86Both crypt16 and bigcrypt are very poor algorithms, btw. Hashing parts
87of the password separately means they can be cracked separately, so
88the double-length hash only doubles the cracking effort instead of
89squaring it. I recommend salted SHA-1 ({SSHA}), or the Blowfish-based
90bcrypt ({CRYPT}$2a$).
91</quote>
92*/
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93
94
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95
96
97/*************************************************
98* Local statics and tables *
99*************************************************/
100
101/* Table of item names, and corresponding switch numbers. The names must be in
102alphabetical order. */
103
104static uschar *item_table[] = {
723c72e6 105 US"acl",
1a46a8c5 106 US"dlfunc",
059ec3d9 107 US"extract",
29f89cad 108 US"filter",
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109 US"hash",
110 US"hmac",
111 US"if",
112 US"length",
aa26e137 113 US"listextract",
059ec3d9 114 US"lookup",
29f89cad 115 US"map",
059ec3d9 116 US"nhash",
1a46a8c5 117 US"perl",
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118 US"prvs",
119 US"prvscheck",
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120 US"readfile",
121 US"readsocket",
29f89cad 122 US"reduce",
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123 US"run",
124 US"sg",
125 US"substr",
126 US"tr" };
127
128enum {
723c72e6 129 EITEM_ACL,
1a46a8c5 130 EITEM_DLFUNC,
059ec3d9 131 EITEM_EXTRACT,
29f89cad 132 EITEM_FILTER,
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133 EITEM_HASH,
134 EITEM_HMAC,
135 EITEM_IF,
136 EITEM_LENGTH,
aa26e137 137 EITEM_LISTEXTRACT,
059ec3d9 138 EITEM_LOOKUP,
29f89cad 139 EITEM_MAP,
059ec3d9 140 EITEM_NHASH,
1a46a8c5 141 EITEM_PERL,
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142 EITEM_PRVS,
143 EITEM_PRVSCHECK,
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144 EITEM_READFILE,
145 EITEM_READSOCK,
29f89cad 146 EITEM_REDUCE,
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147 EITEM_RUN,
148 EITEM_SG,
149 EITEM_SUBSTR,
150 EITEM_TR };
151
152/* Tables of operator names, and corresponding switch numbers. The names must be
153in alphabetical order. There are two tables, because underscore is used in some
154cases to introduce arguments, whereas for other it is part of the name. This is
155an historical mis-design. */
156
157static uschar *op_table_underscore[] = {
158 US"from_utf8",
159 US"local_part",
160 US"quote_local_part",
83e029d5 161 US"reverse_ip",
f90d018c 162 US"time_eval",
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163 US"time_interval"};
164
165enum {
166 EOP_FROM_UTF8,
167 EOP_LOCAL_PART,
168 EOP_QUOTE_LOCAL_PART,
83e029d5 169 EOP_REVERSE_IP,
f90d018c 170 EOP_TIME_EVAL,
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171 EOP_TIME_INTERVAL };
172
173static uschar *op_table_main[] = {
174 US"address",
29f89cad 175 US"addresses",
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176 US"base62",
177 US"base62d",
178 US"domain",
179 US"escape",
180 US"eval",
181 US"eval10",
182 US"expand",
183 US"h",
184 US"hash",
185 US"hex2b64",
c393f931 186 US"hexquote",
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187 US"l",
188 US"lc",
189 US"length",
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190 US"listcount",
191 US"listnamed",
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192 US"mask",
193 US"md5",
194 US"nh",
195 US"nhash",
196 US"quote",
9e3331ea 197 US"randint",
059ec3d9 198 US"rfc2047",
9c57cbc0 199 US"rfc2047d",
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200 US"rxquote",
201 US"s",
202 US"sha1",
203 US"stat",
204 US"str2b64",
205 US"strlen",
206 US"substr",
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207 US"uc",
208 US"utf8clean" };
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209
210enum {
211 EOP_ADDRESS = sizeof(op_table_underscore)/sizeof(uschar *),
29f89cad 212 EOP_ADDRESSES,
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213 EOP_BASE62,
214 EOP_BASE62D,
215 EOP_DOMAIN,
216 EOP_ESCAPE,
217 EOP_EVAL,
218 EOP_EVAL10,
219 EOP_EXPAND,
220 EOP_H,
221 EOP_HASH,
222 EOP_HEX2B64,
c393f931 223 EOP_HEXQUOTE,
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224 EOP_L,
225 EOP_LC,
226 EOP_LENGTH,
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227 EOP_LISTCOUNT,
228 EOP_LISTNAMED,
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229 EOP_MASK,
230 EOP_MD5,
231 EOP_NH,
232 EOP_NHASH,
233 EOP_QUOTE,
9e3331ea 234 EOP_RANDINT,
059ec3d9 235 EOP_RFC2047,
9c57cbc0 236 EOP_RFC2047D,
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237 EOP_RXQUOTE,
238 EOP_S,
239 EOP_SHA1,
240 EOP_STAT,
241 EOP_STR2B64,
242 EOP_STRLEN,
243 EOP_SUBSTR,
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244 EOP_UC,
245 EOP_UTF8CLEAN };
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246
247
248/* Table of condition names, and corresponding switch numbers. The names must
249be in alphabetical order. */
250
251static uschar *cond_table[] = {
252 US"<",
253 US"<=",
254 US"=",
255 US"==", /* Backward compatibility */
256 US">",
257 US">=",
333eea9c 258 US"acl",
059ec3d9 259 US"and",
f3766eb5 260 US"bool",
6a8de854 261 US"bool_lax",
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262 US"crypteq",
263 US"def",
264 US"eq",
265 US"eqi",
266 US"exists",
267 US"first_delivery",
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268 US"forall",
269 US"forany",
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270 US"ge",
271 US"gei",
272 US"gt",
273 US"gti",
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274 US"inlist",
275 US"inlisti",
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276 US"isip",
277 US"isip4",
278 US"isip6",
279 US"ldapauth",
280 US"le",
281 US"lei",
282 US"lt",
283 US"lti",
284 US"match",
285 US"match_address",
286 US"match_domain",
32d668a5 287 US"match_ip",
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288 US"match_local_part",
289 US"or",
290 US"pam",
291 US"pwcheck",
292 US"queue_running",
293 US"radius",
294 US"saslauthd"
295};
296
297enum {
298 ECOND_NUM_L,
299 ECOND_NUM_LE,
300 ECOND_NUM_E,
301 ECOND_NUM_EE,
302 ECOND_NUM_G,
303 ECOND_NUM_GE,
333eea9c 304 ECOND_ACL,
059ec3d9 305 ECOND_AND,
f3766eb5 306 ECOND_BOOL,
6a8de854 307 ECOND_BOOL_LAX,
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308 ECOND_CRYPTEQ,
309 ECOND_DEF,
310 ECOND_STR_EQ,
311 ECOND_STR_EQI,
312 ECOND_EXISTS,
313 ECOND_FIRST_DELIVERY,
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314 ECOND_FORALL,
315 ECOND_FORANY,
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316 ECOND_STR_GE,
317 ECOND_STR_GEI,
318 ECOND_STR_GT,
319 ECOND_STR_GTI,
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320 ECOND_INLIST,
321 ECOND_INLISTI,
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322 ECOND_ISIP,
323 ECOND_ISIP4,
324 ECOND_ISIP6,
325 ECOND_LDAPAUTH,
326 ECOND_STR_LE,
327 ECOND_STR_LEI,
328 ECOND_STR_LT,
329 ECOND_STR_LTI,
330 ECOND_MATCH,
331 ECOND_MATCH_ADDRESS,
332 ECOND_MATCH_DOMAIN,
32d668a5 333 ECOND_MATCH_IP,
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334 ECOND_MATCH_LOCAL_PART,
335 ECOND_OR,
336 ECOND_PAM,
337 ECOND_PWCHECK,
338 ECOND_QUEUE_RUNNING,
339 ECOND_RADIUS,
340 ECOND_SASLAUTHD
341};
342
343
344/* Type for main variable table */
345
346typedef struct {
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347 const char *name;
348 int type;
349 void *value;
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350} var_entry;
351
352/* Type for entries pointing to address/length pairs. Not currently
353in use. */
354
355typedef struct {
356 uschar **address;
357 int *length;
358} alblock;
359
360/* Types of table entry */
361
362enum {
363 vtype_int, /* value is address of int */
364 vtype_filter_int, /* ditto, but recognized only when filtering */
365 vtype_ino, /* value is address of ino_t (not always an int) */
366 vtype_uid, /* value is address of uid_t (not always an int) */
367 vtype_gid, /* value is address of gid_t (not always an int) */
11d7e4fa 368 vtype_bool, /* value is address of bool */
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369 vtype_stringptr, /* value is address of pointer to string */
370 vtype_msgbody, /* as stringptr, but read when first required */
371 vtype_msgbody_end, /* ditto, the end of the message */
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372 vtype_msgheaders, /* the message's headers, processed */
373 vtype_msgheaders_raw, /* the message's headers, unprocessed */
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374 vtype_localpart, /* extract local part from string */
375 vtype_domain, /* extract domain from string */
362145b5 376 vtype_string_func, /* value is string returned by given function */
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377 vtype_todbsdin, /* value not used; generate BSD inbox tod */
378 vtype_tode, /* value not used; generate tod in epoch format */
f5787926 379 vtype_todel, /* value not used; generate tod in epoch/usec format */
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380 vtype_todf, /* value not used; generate full tod */
381 vtype_todl, /* value not used; generate log tod */
382 vtype_todlf, /* value not used; generate log file datestamp tod */
383 vtype_todzone, /* value not used; generate time zone only */
384 vtype_todzulu, /* value not used; generate zulu tod */
385 vtype_reply, /* value not used; get reply from headers */
386 vtype_pid, /* value not used; result is pid */
387 vtype_host_lookup, /* value not used; get host name */
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388 vtype_load_avg, /* value not used; result is int from os_getloadavg */
389 vtype_pspace, /* partition space; value is T/F for spool/log */
8e669ac1 390 vtype_pinodes /* partition inodes; value is T/F for spool/log */
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391 #ifndef DISABLE_DKIM
392 ,vtype_dkim /* Lookup of value in DKIM signature */
393 #endif
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394 };
395
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396static uschar * fn_recipients(void);
397
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398/* This table must be kept in alphabetical order. */
399
400static var_entry var_table[] = {
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401 /* WARNING: Do not invent variables whose names start acl_c or acl_m because
402 they will be confused with user-creatable ACL variables. */
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403 { "acl_arg1", vtype_stringptr, &acl_arg[0] },
404 { "acl_arg2", vtype_stringptr, &acl_arg[1] },
405 { "acl_arg3", vtype_stringptr, &acl_arg[2] },
406 { "acl_arg4", vtype_stringptr, &acl_arg[3] },
407 { "acl_arg5", vtype_stringptr, &acl_arg[4] },
408 { "acl_arg6", vtype_stringptr, &acl_arg[5] },
409 { "acl_arg7", vtype_stringptr, &acl_arg[6] },
410 { "acl_arg8", vtype_stringptr, &acl_arg[7] },
411 { "acl_arg9", vtype_stringptr, &acl_arg[8] },
412 { "acl_narg", vtype_int, &acl_narg },
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413 { "acl_verify_message", vtype_stringptr, &acl_verify_message },
414 { "address_data", vtype_stringptr, &deliver_address_data },
415 { "address_file", vtype_stringptr, &address_file },
416 { "address_pipe", vtype_stringptr, &address_pipe },
2d07a215 417 { "authenticated_fail_id",vtype_stringptr, &authenticated_fail_id },
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418 { "authenticated_id", vtype_stringptr, &authenticated_id },
419 { "authenticated_sender",vtype_stringptr, &authenticated_sender },
420 { "authentication_failed",vtype_int, &authentication_failed },
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421#ifdef WITH_CONTENT_SCAN
422 { "av_failed", vtype_int, &av_failed },
423#endif
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424#ifdef EXPERIMENTAL_BRIGHTMAIL
425 { "bmi_alt_location", vtype_stringptr, &bmi_alt_location },
426 { "bmi_base64_tracker_verdict", vtype_stringptr, &bmi_base64_tracker_verdict },
427 { "bmi_base64_verdict", vtype_stringptr, &bmi_base64_verdict },
428 { "bmi_deliver", vtype_int, &bmi_deliver },
429#endif
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430 { "body_linecount", vtype_int, &body_linecount },
431 { "body_zerocount", vtype_int, &body_zerocount },
432 { "bounce_recipient", vtype_stringptr, &bounce_recipient },
433 { "bounce_return_size_limit", vtype_int, &bounce_return_size_limit },
434 { "caller_gid", vtype_gid, &real_gid },
435 { "caller_uid", vtype_uid, &real_uid },
436 { "compile_date", vtype_stringptr, &version_date },
437 { "compile_number", vtype_stringptr, &version_cnumber },
e5a9dba6 438 { "csa_status", vtype_stringptr, &csa_status },
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439#ifdef EXPERIMENTAL_DCC
440 { "dcc_header", vtype_stringptr, &dcc_header },
441 { "dcc_result", vtype_stringptr, &dcc_result },
442#endif
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443#ifdef WITH_OLD_DEMIME
444 { "demime_errorlevel", vtype_int, &demime_errorlevel },
445 { "demime_reason", vtype_stringptr, &demime_reason },
446#endif
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447#ifndef DISABLE_DKIM
448 { "dkim_algo", vtype_dkim, (void *)DKIM_ALGO },
449 { "dkim_bodylength", vtype_dkim, (void *)DKIM_BODYLENGTH },
450 { "dkim_canon_body", vtype_dkim, (void *)DKIM_CANON_BODY },
451 { "dkim_canon_headers", vtype_dkim, (void *)DKIM_CANON_HEADERS },
452 { "dkim_copiedheaders", vtype_dkim, (void *)DKIM_COPIEDHEADERS },
453 { "dkim_created", vtype_dkim, (void *)DKIM_CREATED },
2df588c9 454 { "dkim_cur_signer", vtype_stringptr, &dkim_cur_signer },
e08d09e5 455 { "dkim_domain", vtype_stringptr, &dkim_signing_domain },
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456 { "dkim_expires", vtype_dkim, (void *)DKIM_EXPIRES },
457 { "dkim_headernames", vtype_dkim, (void *)DKIM_HEADERNAMES },
458 { "dkim_identity", vtype_dkim, (void *)DKIM_IDENTITY },
459 { "dkim_key_granularity",vtype_dkim, (void *)DKIM_KEY_GRANULARITY },
460 { "dkim_key_nosubdomains",vtype_dkim, (void *)DKIM_NOSUBDOMAINS },
461 { "dkim_key_notes", vtype_dkim, (void *)DKIM_KEY_NOTES },
462 { "dkim_key_srvtype", vtype_dkim, (void *)DKIM_KEY_SRVTYPE },
463 { "dkim_key_testing", vtype_dkim, (void *)DKIM_KEY_TESTING },
e08d09e5 464 { "dkim_selector", vtype_stringptr, &dkim_signing_selector },
9e5d6b55 465 { "dkim_signers", vtype_stringptr, &dkim_signers },
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466 { "dkim_verify_reason", vtype_dkim, (void *)DKIM_VERIFY_REASON },
467 { "dkim_verify_status", vtype_dkim, (void *)DKIM_VERIFY_STATUS},
e08d09e5 468#endif
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469#ifdef EXPERIMENTAL_DMARC
470 { "dmarc_ar_header", vtype_stringptr, &dmarc_ar_header },
8c8b8274 471 { "dmarc_domain_policy", vtype_stringptr, &dmarc_domain_policy },
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472 { "dmarc_status", vtype_stringptr, &dmarc_status },
473 { "dmarc_status_text", vtype_stringptr, &dmarc_status_text },
474 { "dmarc_used_domain", vtype_stringptr, &dmarc_used_domain },
475#endif
059ec3d9 476 { "dnslist_domain", vtype_stringptr, &dnslist_domain },
93655c46 477 { "dnslist_matched", vtype_stringptr, &dnslist_matched },
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478 { "dnslist_text", vtype_stringptr, &dnslist_text },
479 { "dnslist_value", vtype_stringptr, &dnslist_value },
480 { "domain", vtype_stringptr, &deliver_domain },
481 { "domain_data", vtype_stringptr, &deliver_domain_data },
482 { "exim_gid", vtype_gid, &exim_gid },
483 { "exim_path", vtype_stringptr, &exim_path },
484 { "exim_uid", vtype_uid, &exim_uid },
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485#ifdef WITH_OLD_DEMIME
486 { "found_extension", vtype_stringptr, &found_extension },
8e669ac1 487#endif
362145b5 488 { "headers_added", vtype_string_func, &fn_hdrs_added },
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489 { "home", vtype_stringptr, &deliver_home },
490 { "host", vtype_stringptr, &deliver_host },
491 { "host_address", vtype_stringptr, &deliver_host_address },
492 { "host_data", vtype_stringptr, &host_data },
b08b24c8 493 { "host_lookup_deferred",vtype_int, &host_lookup_deferred },
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494 { "host_lookup_failed", vtype_int, &host_lookup_failed },
495 { "inode", vtype_ino, &deliver_inode },
496 { "interface_address", vtype_stringptr, &interface_address },
497 { "interface_port", vtype_int, &interface_port },
0ce9abe6 498 { "item", vtype_stringptr, &iterate_item },
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499 #ifdef LOOKUP_LDAP
500 { "ldap_dn", vtype_stringptr, &eldap_dn },
501 #endif
502 { "load_average", vtype_load_avg, NULL },
503 { "local_part", vtype_stringptr, &deliver_localpart },
504 { "local_part_data", vtype_stringptr, &deliver_localpart_data },
505 { "local_part_prefix", vtype_stringptr, &deliver_localpart_prefix },
506 { "local_part_suffix", vtype_stringptr, &deliver_localpart_suffix },
507 { "local_scan_data", vtype_stringptr, &local_scan_data },
508 { "local_user_gid", vtype_gid, &local_user_gid },
509 { "local_user_uid", vtype_uid, &local_user_uid },
510 { "localhost_number", vtype_int, &host_number },
5cb8cbc6 511 { "log_inodes", vtype_pinodes, (void *)FALSE },
8e669ac1 512 { "log_space", vtype_pspace, (void *)FALSE },
059ec3d9 513 { "mailstore_basename", vtype_stringptr, &mailstore_basename },
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514#ifdef WITH_CONTENT_SCAN
515 { "malware_name", vtype_stringptr, &malware_name },
516#endif
d677b2f2 517 { "max_received_linelength", vtype_int, &max_received_linelength },
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518 { "message_age", vtype_int, &message_age },
519 { "message_body", vtype_msgbody, &message_body },
520 { "message_body_end", vtype_msgbody_end, &message_body_end },
521 { "message_body_size", vtype_int, &message_body_size },
1ab52c69 522 { "message_exim_id", vtype_stringptr, &message_id },
059ec3d9 523 { "message_headers", vtype_msgheaders, NULL },
ff75a1f7 524 { "message_headers_raw", vtype_msgheaders_raw, NULL },
059ec3d9 525 { "message_id", vtype_stringptr, &message_id },
2e0c1448 526 { "message_linecount", vtype_int, &message_linecount },
059ec3d9 527 { "message_size", vtype_int, &message_size },
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528#ifdef WITH_CONTENT_SCAN
529 { "mime_anomaly_level", vtype_int, &mime_anomaly_level },
530 { "mime_anomaly_text", vtype_stringptr, &mime_anomaly_text },
531 { "mime_boundary", vtype_stringptr, &mime_boundary },
532 { "mime_charset", vtype_stringptr, &mime_charset },
533 { "mime_content_description", vtype_stringptr, &mime_content_description },
534 { "mime_content_disposition", vtype_stringptr, &mime_content_disposition },
535 { "mime_content_id", vtype_stringptr, &mime_content_id },
536 { "mime_content_size", vtype_int, &mime_content_size },
537 { "mime_content_transfer_encoding",vtype_stringptr, &mime_content_transfer_encoding },
538 { "mime_content_type", vtype_stringptr, &mime_content_type },
539 { "mime_decoded_filename", vtype_stringptr, &mime_decoded_filename },
540 { "mime_filename", vtype_stringptr, &mime_filename },
541 { "mime_is_coverletter", vtype_int, &mime_is_coverletter },
542 { "mime_is_multipart", vtype_int, &mime_is_multipart },
543 { "mime_is_rfc822", vtype_int, &mime_is_rfc822 },
544 { "mime_part_count", vtype_int, &mime_part_count },
545#endif
059ec3d9
PH
546 { "n0", vtype_filter_int, &filter_n[0] },
547 { "n1", vtype_filter_int, &filter_n[1] },
548 { "n2", vtype_filter_int, &filter_n[2] },
549 { "n3", vtype_filter_int, &filter_n[3] },
550 { "n4", vtype_filter_int, &filter_n[4] },
551 { "n5", vtype_filter_int, &filter_n[5] },
552 { "n6", vtype_filter_int, &filter_n[6] },
553 { "n7", vtype_filter_int, &filter_n[7] },
554 { "n8", vtype_filter_int, &filter_n[8] },
555 { "n9", vtype_filter_int, &filter_n[9] },
556 { "original_domain", vtype_stringptr, &deliver_domain_orig },
557 { "original_local_part", vtype_stringptr, &deliver_localpart_orig },
558 { "originator_gid", vtype_gid, &originator_gid },
559 { "originator_uid", vtype_uid, &originator_uid },
560 { "parent_domain", vtype_stringptr, &deliver_domain_parent },
561 { "parent_local_part", vtype_stringptr, &deliver_localpart_parent },
562 { "pid", vtype_pid, NULL },
563 { "primary_hostname", vtype_stringptr, &primary_hostname },
a3c86431 564#ifdef EXPERIMENTAL_PROXY
a3bddaa8
TL
565 { "proxy_host_address", vtype_stringptr, &proxy_host_address },
566 { "proxy_host_port", vtype_int, &proxy_host_port },
a3c86431 567 { "proxy_session", vtype_bool, &proxy_session },
eb57651e
TL
568 { "proxy_target_address",vtype_stringptr, &proxy_target_address },
569 { "proxy_target_port", vtype_int, &proxy_target_port },
a3c86431 570#endif
fffda43a
TK
571 { "prvscheck_address", vtype_stringptr, &prvscheck_address },
572 { "prvscheck_keynum", vtype_stringptr, &prvscheck_keynum },
573 { "prvscheck_result", vtype_stringptr, &prvscheck_result },
059ec3d9
PH
574 { "qualify_domain", vtype_stringptr, &qualify_domain_sender },
575 { "qualify_recipient", vtype_stringptr, &qualify_domain_recipient },
576 { "rcpt_count", vtype_int, &rcpt_count },
577 { "rcpt_defer_count", vtype_int, &rcpt_defer_count },
578 { "rcpt_fail_count", vtype_int, &rcpt_fail_count },
579 { "received_count", vtype_int, &received_count },
580 { "received_for", vtype_stringptr, &received_for },
194cc0e4
PH
581 { "received_ip_address", vtype_stringptr, &interface_address },
582 { "received_port", vtype_int, &interface_port },
059ec3d9 583 { "received_protocol", vtype_stringptr, &received_protocol },
7dbf77c9 584 { "received_time", vtype_int, &received_time },
059ec3d9 585 { "recipient_data", vtype_stringptr, &recipient_data },
8e669ac1 586 { "recipient_verify_failure",vtype_stringptr,&recipient_verify_failure },
362145b5 587 { "recipients", vtype_string_func, &fn_recipients },
059ec3d9 588 { "recipients_count", vtype_int, &recipients_count },
8523533c
TK
589#ifdef WITH_CONTENT_SCAN
590 { "regex_match_string", vtype_stringptr, &regex_match_string },
591#endif
059ec3d9
PH
592 { "reply_address", vtype_reply, NULL },
593 { "return_path", vtype_stringptr, &return_path },
594 { "return_size_limit", vtype_int, &bounce_return_size_limit },
181d9bf8 595 { "router_name", vtype_stringptr, &router_name },
059ec3d9
PH
596 { "runrc", vtype_int, &runrc },
597 { "self_hostname", vtype_stringptr, &self_hostname },
598 { "sender_address", vtype_stringptr, &sender_address },
2a3eea10 599 { "sender_address_data", vtype_stringptr, &sender_address_data },
059ec3d9
PH
600 { "sender_address_domain", vtype_domain, &sender_address },
601 { "sender_address_local_part", vtype_localpart, &sender_address },
602 { "sender_data", vtype_stringptr, &sender_data },
603 { "sender_fullhost", vtype_stringptr, &sender_fullhost },
604 { "sender_helo_name", vtype_stringptr, &sender_helo_name },
605 { "sender_host_address", vtype_stringptr, &sender_host_address },
606 { "sender_host_authenticated",vtype_stringptr, &sender_host_authenticated },
11d7e4fa 607 { "sender_host_dnssec", vtype_bool, &sender_host_dnssec },
059ec3d9
PH
608 { "sender_host_name", vtype_host_lookup, NULL },
609 { "sender_host_port", vtype_int, &sender_host_port },
610 { "sender_ident", vtype_stringptr, &sender_ident },
870f6ba8
TF
611 { "sender_rate", vtype_stringptr, &sender_rate },
612 { "sender_rate_limit", vtype_stringptr, &sender_rate_limit },
613 { "sender_rate_period", vtype_stringptr, &sender_rate_period },
059ec3d9 614 { "sender_rcvhost", vtype_stringptr, &sender_rcvhost },
8e669ac1 615 { "sender_verify_failure",vtype_stringptr, &sender_verify_failure },
41c7c167
PH
616 { "sending_ip_address", vtype_stringptr, &sending_ip_address },
617 { "sending_port", vtype_int, &sending_port },
8e669ac1 618 { "smtp_active_hostname", vtype_stringptr, &smtp_active_hostname },
3ee512ff
PH
619 { "smtp_command", vtype_stringptr, &smtp_cmd_buffer },
620 { "smtp_command_argument", vtype_stringptr, &smtp_cmd_argument },
b01dd148 621 { "smtp_count_at_connection_start", vtype_int, &smtp_accept_count },
8f128379 622 { "smtp_notquit_reason", vtype_stringptr, &smtp_notquit_reason },
059ec3d9
PH
623 { "sn0", vtype_filter_int, &filter_sn[0] },
624 { "sn1", vtype_filter_int, &filter_sn[1] },
625 { "sn2", vtype_filter_int, &filter_sn[2] },
626 { "sn3", vtype_filter_int, &filter_sn[3] },
627 { "sn4", vtype_filter_int, &filter_sn[4] },
628 { "sn5", vtype_filter_int, &filter_sn[5] },
629 { "sn6", vtype_filter_int, &filter_sn[6] },
630 { "sn7", vtype_filter_int, &filter_sn[7] },
631 { "sn8", vtype_filter_int, &filter_sn[8] },
632 { "sn9", vtype_filter_int, &filter_sn[9] },
8523533c
TK
633#ifdef WITH_CONTENT_SCAN
634 { "spam_bar", vtype_stringptr, &spam_bar },
635 { "spam_report", vtype_stringptr, &spam_report },
636 { "spam_score", vtype_stringptr, &spam_score },
637 { "spam_score_int", vtype_stringptr, &spam_score_int },
638#endif
639#ifdef EXPERIMENTAL_SPF
65a7d8c3 640 { "spf_guess", vtype_stringptr, &spf_guess },
8523533c
TK
641 { "spf_header_comment", vtype_stringptr, &spf_header_comment },
642 { "spf_received", vtype_stringptr, &spf_received },
643 { "spf_result", vtype_stringptr, &spf_result },
644 { "spf_smtp_comment", vtype_stringptr, &spf_smtp_comment },
645#endif
059ec3d9 646 { "spool_directory", vtype_stringptr, &spool_directory },
5cb8cbc6 647 { "spool_inodes", vtype_pinodes, (void *)TRUE },
8e669ac1 648 { "spool_space", vtype_pspace, (void *)TRUE },
8523533c
TK
649#ifdef EXPERIMENTAL_SRS
650 { "srs_db_address", vtype_stringptr, &srs_db_address },
651 { "srs_db_key", vtype_stringptr, &srs_db_key },
652 { "srs_orig_recipient", vtype_stringptr, &srs_orig_recipient },
653 { "srs_orig_sender", vtype_stringptr, &srs_orig_sender },
654 { "srs_recipient", vtype_stringptr, &srs_recipient },
655 { "srs_status", vtype_stringptr, &srs_status },
656#endif
059ec3d9 657 { "thisaddress", vtype_stringptr, &filter_thisaddress },
817d9f57 658
d9b2312b 659 /* The non-(in,out) variables are now deprecated */
817d9f57
JH
660 { "tls_bits", vtype_int, &tls_in.bits },
661 { "tls_certificate_verified", vtype_int, &tls_in.certificate_verified },
662 { "tls_cipher", vtype_stringptr, &tls_in.cipher },
d9b2312b
JH
663
664 { "tls_in_bits", vtype_int, &tls_in.bits },
665 { "tls_in_certificate_verified", vtype_int, &tls_in.certificate_verified },
666 { "tls_in_cipher", vtype_stringptr, &tls_in.cipher },
667 { "tls_in_peerdn", vtype_stringptr, &tls_in.peerdn },
668#if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
669 { "tls_in_sni", vtype_stringptr, &tls_in.sni },
670#endif
817d9f57 671 { "tls_out_bits", vtype_int, &tls_out.bits },
cb9d95ae 672 { "tls_out_certificate_verified", vtype_int,&tls_out.certificate_verified },
817d9f57
JH
673 { "tls_out_cipher", vtype_stringptr, &tls_out.cipher },
674 { "tls_out_peerdn", vtype_stringptr, &tls_out.peerdn },
675#if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
676 { "tls_out_sni", vtype_stringptr, &tls_out.sni },
7be682ca 677#endif
d9b2312b 678
613dd4ae
JH
679 { "tls_peerdn", vtype_stringptr, &tls_in.peerdn }, /* mind the alphabetical order! */
680#if defined(SUPPORT_TLS) && !defined(USE_GNUTLS)
681 { "tls_sni", vtype_stringptr, &tls_in.sni }, /* mind the alphabetical order! */
682#endif
817d9f57 683
059ec3d9
PH
684 { "tod_bsdinbox", vtype_todbsdin, NULL },
685 { "tod_epoch", vtype_tode, NULL },
f5787926 686 { "tod_epoch_l", vtype_todel, NULL },
059ec3d9
PH
687 { "tod_full", vtype_todf, NULL },
688 { "tod_log", vtype_todl, NULL },
689 { "tod_logfile", vtype_todlf, NULL },
690 { "tod_zone", vtype_todzone, NULL },
691 { "tod_zulu", vtype_todzulu, NULL },
d68218c7
JH
692#ifdef EXPERIMENTAL_TPDA
693 { "tpda_defer_errno", vtype_int, &tpda_defer_errno },
694 { "tpda_defer_errstr", vtype_stringptr, &tpda_defer_errstr },
695 { "tpda_delivery_confirmation", vtype_stringptr, &tpda_delivery_confirmation },
696 { "tpda_delivery_domain", vtype_stringptr, &tpda_delivery_domain },
697 { "tpda_delivery_fqdn", vtype_stringptr, &tpda_delivery_fqdn },
698 { "tpda_delivery_ip", vtype_stringptr, &tpda_delivery_ip },
699 { "tpda_delivery_local_part",vtype_stringptr,&tpda_delivery_local_part },
700 { "tpda_delivery_port", vtype_int, &tpda_delivery_port },
701#endif
181d9bf8 702 { "transport_name", vtype_stringptr, &transport_name },
059ec3d9
PH
703 { "value", vtype_stringptr, &lookup_value },
704 { "version_number", vtype_stringptr, &version_string },
705 { "warn_message_delay", vtype_stringptr, &warnmsg_delay },
706 { "warn_message_recipient",vtype_stringptr, &warnmsg_recipients },
707 { "warn_message_recipients",vtype_stringptr,&warnmsg_recipients },
708 { "warnmsg_delay", vtype_stringptr, &warnmsg_delay },
709 { "warnmsg_recipient", vtype_stringptr, &warnmsg_recipients },
710 { "warnmsg_recipients", vtype_stringptr, &warnmsg_recipients }
711};
712
713static int var_table_size = sizeof(var_table)/sizeof(var_entry);
714static uschar var_buffer[256];
715static BOOL malformed_header;
716
717/* For textual hashes */
718
1ba28e2b
PP
719static const char *hashcodes = "abcdefghijklmnopqrtsuvwxyz"
720 "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
721 "0123456789";
059ec3d9
PH
722
723enum { HMAC_MD5, HMAC_SHA1 };
724
725/* For numeric hashes */
726
727static unsigned int prime[] = {
728 2, 3, 5, 7, 11, 13, 17, 19, 23, 29,
729 31, 37, 41, 43, 47, 53, 59, 61, 67, 71,
730 73, 79, 83, 89, 97, 101, 103, 107, 109, 113};
731
732/* For printing modes in symbolic form */
733
734static uschar *mtable_normal[] =
735 { US"---", US"--x", US"-w-", US"-wx", US"r--", US"r-x", US"rw-", US"rwx" };
736
737static uschar *mtable_setid[] =
738 { US"--S", US"--s", US"-wS", US"-ws", US"r-S", US"r-s", US"rwS", US"rws" };
739
740static uschar *mtable_sticky[] =
741 { US"--T", US"--t", US"-wT", US"-wt", US"r-T", US"r-t", US"rwT", US"rwt" };
742
743
744
745/*************************************************
746* Tables for UTF-8 support *
747*************************************************/
748
749/* Table of the number of extra characters, indexed by the first character
750masked with 0x3f. The highest number for a valid UTF-8 character is in fact
7510x3d. */
752
753static uschar utf8_table1[] = {
754 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
755 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
756 2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,
757 3,3,3,3,3,3,3,3,4,4,4,4,5,5,5,5 };
758
759/* These are the masks for the data bits in the first byte of a character,
760indexed by the number of additional bytes. */
761
762static int utf8_table2[] = { 0xff, 0x1f, 0x0f, 0x07, 0x03, 0x01};
763
764/* Get the next UTF-8 character, advancing the pointer. */
765
766#define GETUTF8INC(c, ptr) \
767 c = *ptr++; \
768 if ((c & 0xc0) == 0xc0) \
769 { \
770 int a = utf8_table1[c & 0x3f]; /* Number of additional bytes */ \
771 int s = 6*a; \
772 c = (c & utf8_table2[a]) << s; \
773 while (a-- > 0) \
774 { \
775 s -= 6; \
776 c |= (*ptr++ & 0x3f) << s; \
777 } \
778 }
779
780
781/*************************************************
782* Binary chop search on a table *
783*************************************************/
784
785/* This is used for matching expansion items and operators.
786
787Arguments:
788 name the name that is being sought
789 table the table to search
790 table_size the number of items in the table
791
792Returns: the offset in the table, or -1
793*/
794
795static int
796chop_match(uschar *name, uschar **table, int table_size)
797{
798uschar **bot = table;
799uschar **top = table + table_size;
800
801while (top > bot)
802 {
803 uschar **mid = bot + (top - bot)/2;
804 int c = Ustrcmp(name, *mid);
805 if (c == 0) return mid - table;
806 if (c > 0) bot = mid + 1; else top = mid;
807 }
808
809return -1;
810}
811
812
813
814/*************************************************
815* Check a condition string *
816*************************************************/
817
818/* This function is called to expand a string, and test the result for a "true"
819or "false" value. Failure of the expansion yields FALSE; logged unless it was a
be7a5781
JH
820forced fail or lookup defer.
821
822We used to release all store used, but this is not not safe due
823to ${dlfunc } and ${acl }. In any case expand_string_internal()
824is reasonably careful to release what it can.
059ec3d9 825
6a8de854
PP
826The actual false-value tests should be replicated for ECOND_BOOL_LAX.
827
059ec3d9
PH
828Arguments:
829 condition the condition string
830 m1 text to be incorporated in panic error
831 m2 ditto
832
833Returns: TRUE if condition is met, FALSE if not
834*/
835
836BOOL
837expand_check_condition(uschar *condition, uschar *m1, uschar *m2)
838{
839int rc;
059ec3d9
PH
840uschar *ss = expand_string(condition);
841if (ss == NULL)
842 {
843 if (!expand_string_forcedfail && !search_find_defer)
844 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand condition \"%s\" "
845 "for %s %s: %s", condition, m1, m2, expand_string_message);
846 return FALSE;
847 }
848rc = ss[0] != 0 && Ustrcmp(ss, "0") != 0 && strcmpic(ss, US"no") != 0 &&
849 strcmpic(ss, US"false") != 0;
059ec3d9
PH
850return rc;
851}
852
853
854
17c76198 855
059ec3d9 856/*************************************************
9e3331ea
TK
857* Pseudo-random number generation *
858*************************************************/
859
860/* Pseudo-random number generation. The result is not "expected" to be
861cryptographically strong but not so weak that someone will shoot themselves
862in the foot using it as a nonce in some email header scheme or whatever
863weirdness they'll twist this into. The result should ideally handle fork().
864
865However, if we're stuck unable to provide this, then we'll fall back to
866appallingly bad randomness.
867
17c76198
PP
868If SUPPORT_TLS is defined then this will not be used except as an emergency
869fallback.
9e3331ea
TK
870
871Arguments:
872 max range maximum
873Returns a random number in range [0, max-1]
874*/
875
17c76198
PP
876#ifdef SUPPORT_TLS
877# define vaguely_random_number vaguely_random_number_fallback
878#endif
9e3331ea 879int
17c76198 880vaguely_random_number(int max)
9e3331ea 881{
17c76198
PP
882#ifdef SUPPORT_TLS
883# undef vaguely_random_number
884#endif
9e3331ea
TK
885 static pid_t pid = 0;
886 pid_t p2;
887#if defined(HAVE_SRANDOM) && !defined(HAVE_SRANDOMDEV)
888 struct timeval tv;
889#endif
890
891 p2 = getpid();
892 if (p2 != pid)
893 {
894 if (pid != 0)
895 {
896
897#ifdef HAVE_ARC4RANDOM
898 /* cryptographically strong randomness, common on *BSD platforms, not
899 so much elsewhere. Alas. */
900 arc4random_stir();
901#elif defined(HAVE_SRANDOM) || defined(HAVE_SRANDOMDEV)
902#ifdef HAVE_SRANDOMDEV
903 /* uses random(4) for seeding */
904 srandomdev();
905#else
906 gettimeofday(&tv, NULL);
907 srandom(tv.tv_sec | tv.tv_usec | getpid());
908#endif
909#else
910 /* Poor randomness and no seeding here */
911#endif
912
913 }
914 pid = p2;
915 }
916
917#ifdef HAVE_ARC4RANDOM
918 return arc4random() % max;
919#elif defined(HAVE_SRANDOM) || defined(HAVE_SRANDOMDEV)
920 return random() % max;
921#else
922 /* This one returns a 16-bit number, definitely not crypto-strong */
923 return random_number(max);
924#endif
925}
926
17c76198
PP
927
928
9e3331ea
TK
929
930/*************************************************
059ec3d9
PH
931* Pick out a name from a string *
932*************************************************/
933
934/* If the name is too long, it is silently truncated.
935
936Arguments:
937 name points to a buffer into which to put the name
938 max is the length of the buffer
939 s points to the first alphabetic character of the name
940 extras chars other than alphanumerics to permit
941
942Returns: pointer to the first character after the name
943
944Note: The test for *s != 0 in the while loop is necessary because
945Ustrchr() yields non-NULL if the character is zero (which is not something
946I expected). */
947
948static uschar *
949read_name(uschar *name, int max, uschar *s, uschar *extras)
950{
951int ptr = 0;
952while (*s != 0 && (isalnum(*s) || Ustrchr(extras, *s) != NULL))
953 {
954 if (ptr < max-1) name[ptr++] = *s;
955 s++;
956 }
957name[ptr] = 0;
958return s;
959}
960
961
962
963/*************************************************
964* Pick out the rest of a header name *
965*************************************************/
966
967/* A variable name starting $header_ (or just $h_ for those who like
968abbreviations) might not be the complete header name because headers can
969contain any printing characters in their names, except ':'. This function is
970called to read the rest of the name, chop h[eader]_ off the front, and put ':'
971on the end, if the name was terminated by white space.
972
973Arguments:
974 name points to a buffer in which the name read so far exists
975 max is the length of the buffer
976 s points to the first character after the name so far, i.e. the
977 first non-alphameric character after $header_xxxxx
978
979Returns: a pointer to the first character after the header name
980*/
981
982static uschar *
983read_header_name(uschar *name, int max, uschar *s)
984{
985int prelen = Ustrchr(name, '_') - name + 1;
986int ptr = Ustrlen(name) - prelen;
987if (ptr > 0) memmove(name, name+prelen, ptr);
988while (mac_isgraph(*s) && *s != ':')
989 {
990 if (ptr < max-1) name[ptr++] = *s;
991 s++;
992 }
993if (*s == ':') s++;
994name[ptr++] = ':';
995name[ptr] = 0;
996return s;
997}
998
999
1000
1001/*************************************************
1002* Pick out a number from a string *
1003*************************************************/
1004
1005/* Arguments:
1006 n points to an integer into which to put the number
1007 s points to the first digit of the number
1008
1009Returns: a pointer to the character after the last digit
1010*/
1011
1012static uschar *
1013read_number(int *n, uschar *s)
1014{
1015*n = 0;
1016while (isdigit(*s)) *n = *n * 10 + (*s++ - '0');
1017return s;
1018}
1019
1020
1021
1022/*************************************************
1023* Extract keyed subfield from a string *
1024*************************************************/
1025
1026/* The yield is in dynamic store; NULL means that the key was not found.
1027
1028Arguments:
1029 key points to the name of the key
1030 s points to the string from which to extract the subfield
1031
1032Returns: NULL if the subfield was not found, or
1033 a pointer to the subfield's data
1034*/
1035
1036static uschar *
1037expand_getkeyed(uschar *key, uschar *s)
1038{
1039int length = Ustrlen(key);
1040while (isspace(*s)) s++;
1041
1042/* Loop to search for the key */
1043
1044while (*s != 0)
1045 {
1046 int dkeylength;
1047 uschar *data;
1048 uschar *dkey = s;
1049
1050 while (*s != 0 && *s != '=' && !isspace(*s)) s++;
1051 dkeylength = s - dkey;
1052 while (isspace(*s)) s++;
1053 if (*s == '=') while (isspace((*(++s))));
1054
1055 data = string_dequote(&s);
1056 if (length == dkeylength && strncmpic(key, dkey, length) == 0)
1057 return data;
1058
1059 while (isspace(*s)) s++;
1060 }
1061
1062return NULL;
1063}
1064
1065
1066
1067
1068/*************************************************
1069* Extract numbered subfield from string *
1070*************************************************/
1071
1072/* Extracts a numbered field from a string that is divided by tokens - for
1073example a line from /etc/passwd is divided by colon characters. First field is
1074numbered one. Negative arguments count from the right. Zero returns the whole
1075string. Returns NULL if there are insufficient tokens in the string
1076
1077***WARNING***
1078Modifies final argument - this is a dynamically generated string, so that's OK.
1079
1080Arguments:
1081 field number of field to be extracted,
1082 first field = 1, whole string = 0, last field = -1
1083 separators characters that are used to break string into tokens
1084 s points to the string from which to extract the subfield
1085
1086Returns: NULL if the field was not found,
1087 a pointer to the field's data inside s (modified to add 0)
1088*/
1089
1090static uschar *
1091expand_gettokened (int field, uschar *separators, uschar *s)
1092{
1093int sep = 1;
1094int count;
1095uschar *ss = s;
1096uschar *fieldtext = NULL;
1097
1098if (field == 0) return s;
1099
1100/* Break the line up into fields in place; for field > 0 we stop when we have
1101done the number of fields we want. For field < 0 we continue till the end of
1102the string, counting the number of fields. */
1103
1104count = (field > 0)? field : INT_MAX;
1105
1106while (count-- > 0)
1107 {
1108 size_t len;
1109
1110 /* Previous field was the last one in the string. For a positive field
1111 number, this means there are not enough fields. For a negative field number,
1112 check that there are enough, and scan back to find the one that is wanted. */
1113
1114 if (sep == 0)
1115 {
1116 if (field > 0 || (-field) > (INT_MAX - count - 1)) return NULL;
1117 if ((-field) == (INT_MAX - count - 1)) return s;
1118 while (field++ < 0)
1119 {
1120 ss--;
1121 while (ss[-1] != 0) ss--;
1122 }
1123 fieldtext = ss;
1124 break;
1125 }
1126
1127 /* Previous field was not last in the string; save its start and put a
1128 zero at its end. */
1129
1130 fieldtext = ss;
1131 len = Ustrcspn(ss, separators);
1132 sep = ss[len];
1133 ss[len] = 0;
1134 ss += len + 1;
1135 }
1136
1137return fieldtext;
1138}
1139
1140
aa26e137
JH
1141static uschar *
1142expand_getlistele (int field, uschar *list)
1143{
1144uschar * tlist= list;
1145int sep= 0;
1146uschar dummy;
1147
1148if(field<0)
1149{
1150 for(field++; string_nextinlist(&tlist, &sep, &dummy, 1); ) field++;
1151 sep= 0;
1152}
1153if(field==0) return NULL;
1154while(--field>0 && (string_nextinlist(&list, &sep, &dummy, 1))) ;
1155return string_nextinlist(&list, &sep, NULL, 0);
1156}
059ec3d9
PH
1157
1158/*************************************************
1159* Extract a substring from a string *
1160*************************************************/
1161
1162/* Perform the ${substr or ${length expansion operations.
1163
1164Arguments:
1165 subject the input string
1166 value1 the offset from the start of the input string to the start of
1167 the output string; if negative, count from the right.
1168 value2 the length of the output string, or negative (-1) for unset
1169 if value1 is positive, unset means "all after"
1170 if value1 is negative, unset means "all before"
1171 len set to the length of the returned string
1172
1173Returns: pointer to the output string, or NULL if there is an error
1174*/
1175
1176static uschar *
1177extract_substr(uschar *subject, int value1, int value2, int *len)
1178{
1179int sublen = Ustrlen(subject);
1180
1181if (value1 < 0) /* count from right */
1182 {
1183 value1 += sublen;
1184
1185 /* If the position is before the start, skip to the start, and adjust the
1186 length. If the length ends up negative, the substring is null because nothing
1187 can precede. This falls out naturally when the length is unset, meaning "all
1188 to the left". */
1189
1190 if (value1 < 0)
1191 {
1192 value2 += value1;
1193 if (value2 < 0) value2 = 0;
1194 value1 = 0;
1195 }
1196
1197 /* Otherwise an unset length => characters before value1 */
1198
1199 else if (value2 < 0)
1200 {
1201 value2 = value1;
1202 value1 = 0;
1203 }
1204 }
1205
1206/* For a non-negative offset, if the starting position is past the end of the
1207string, the result will be the null string. Otherwise, an unset length means
1208"rest"; just set it to the maximum - it will be cut down below if necessary. */
1209
1210else
1211 {
1212 if (value1 > sublen)
1213 {
1214 value1 = sublen;
1215 value2 = 0;
1216 }
1217 else if (value2 < 0) value2 = sublen;
1218 }
1219
1220/* Cut the length down to the maximum possible for the offset value, and get
1221the required characters. */
1222
1223if (value1 + value2 > sublen) value2 = sublen - value1;
1224*len = value2;
1225return subject + value1;
1226}
1227
1228
1229
1230
1231/*************************************************
1232* Old-style hash of a string *
1233*************************************************/
1234
1235/* Perform the ${hash expansion operation.
1236
1237Arguments:
1238 subject the input string (an expanded substring)
1239 value1 the length of the output string; if greater or equal to the
1240 length of the input string, the input string is returned
1241 value2 the number of hash characters to use, or 26 if negative
1242 len set to the length of the returned string
1243
1244Returns: pointer to the output string, or NULL if there is an error
1245*/
1246
1247static uschar *
1248compute_hash(uschar *subject, int value1, int value2, int *len)
1249{
1250int sublen = Ustrlen(subject);
1251
1252if (value2 < 0) value2 = 26;
1253else if (value2 > Ustrlen(hashcodes))
1254 {
1255 expand_string_message =
1256 string_sprintf("hash count \"%d\" too big", value2);
1257 return NULL;
1258 }
1259
1260/* Calculate the hash text. We know it is shorter than the original string, so
1261can safely place it in subject[] (we know that subject is always itself an
1262expanded substring). */
1263
1264if (value1 < sublen)
1265 {
1266 int c;
1267 int i = 0;
1268 int j = value1;
1269 while ((c = (subject[j])) != 0)
1270 {
1271 int shift = (c + j++) & 7;
1272 subject[i] ^= (c << shift) | (c >> (8-shift));
1273 if (++i >= value1) i = 0;
1274 }
1275 for (i = 0; i < value1; i++)
1276 subject[i] = hashcodes[(subject[i]) % value2];
1277 }
1278else value1 = sublen;
1279
1280*len = value1;
1281return subject;
1282}
1283
1284
1285
1286
1287/*************************************************
1288* Numeric hash of a string *
1289*************************************************/
1290
1291/* Perform the ${nhash expansion operation. The first characters of the
1292string are treated as most important, and get the highest prime numbers.
1293
1294Arguments:
1295 subject the input string
1296 value1 the maximum value of the first part of the result
1297 value2 the maximum value of the second part of the result,
1298 or negative to produce only a one-part result
1299 len set to the length of the returned string
1300
1301Returns: pointer to the output string, or NULL if there is an error.
1302*/
1303
1304static uschar *
1305compute_nhash (uschar *subject, int value1, int value2, int *len)
1306{
1307uschar *s = subject;
1308int i = 0;
1309unsigned long int total = 0; /* no overflow */
1310
1311while (*s != 0)
1312 {
1313 if (i == 0) i = sizeof(prime)/sizeof(int) - 1;
1314 total += prime[i--] * (unsigned int)(*s++);
1315 }
1316
1317/* If value2 is unset, just compute one number */
1318
1319if (value2 < 0)
1320 {
1321 s = string_sprintf("%d", total % value1);
1322 }
1323
1324/* Otherwise do a div/mod hash */
1325
1326else
1327 {
1328 total = total % (value1 * value2);
1329 s = string_sprintf("%d/%d", total/value2, total % value2);
1330 }
1331
1332*len = Ustrlen(s);
1333return s;
1334}
1335
1336
1337
1338
1339
1340/*************************************************
1341* Find the value of a header or headers *
1342*************************************************/
1343
1344/* Multiple instances of the same header get concatenated, and this function
1345can also return a concatenation of all the header lines. When concatenating
1346specific headers that contain lists of addresses, a comma is inserted between
1347them. Otherwise we use a straight concatenation. Because some messages can have
1348pathologically large number of lines, there is a limit on the length that is
1349returned. Also, to avoid massive store use which would result from using
1350string_cat() as it copies and extends strings, we do a preliminary pass to find
1351out exactly how much store will be needed. On "normal" messages this will be
1352pretty trivial.
1353
1354Arguments:
1355 name the name of the header, without the leading $header_ or $h_,
1356 or NULL if a concatenation of all headers is required
1357 exists_only TRUE if called from a def: test; don't need to build a string;
1358 just return a string that is not "" and not "0" if the header
1359 exists
1360 newsize return the size of memory block that was obtained; may be NULL
1361 if exists_only is TRUE
1362 want_raw TRUE if called for $rh_ or $rheader_ variables; no processing,
ff75a1f7
PH
1363 other than concatenating, will be done on the header. Also used
1364 for $message_headers_raw.
059ec3d9
PH
1365 charset name of charset to translate MIME words to; used only if
1366 want_raw is false; if NULL, no translation is done (this is
1367 used for $bh_ and $bheader_)
1368
1369Returns: NULL if the header does not exist, else a pointer to a new
1370 store block
1371*/
1372
1373static uschar *
1374find_header(uschar *name, BOOL exists_only, int *newsize, BOOL want_raw,
1375 uschar *charset)
1376{
1377BOOL found = name == NULL;
1378int comma = 0;
1379int len = found? 0 : Ustrlen(name);
1380int i;
1381uschar *yield = NULL;
1382uschar *ptr = NULL;
1383
1384/* Loop for two passes - saves code repetition */
1385
1386for (i = 0; i < 2; i++)
1387 {
1388 int size = 0;
1389 header_line *h;
1390
1391 for (h = header_list; size < header_insert_maxlen && h != NULL; h = h->next)
1392 {
1393 if (h->type != htype_old && h->text != NULL) /* NULL => Received: placeholder */
1394 {
1395 if (name == NULL || (len <= h->slen && strncmpic(name, h->text, len) == 0))
1396 {
1397 int ilen;
1398 uschar *t;
1399
1400 if (exists_only) return US"1"; /* don't need actual string */
1401 found = TRUE;
1402 t = h->text + len; /* text to insert */
1403 if (!want_raw) /* unless wanted raw, */
1404 while (isspace(*t)) t++; /* remove leading white space */
1405 ilen = h->slen - (t - h->text); /* length to insert */
1406
fd700877
PH
1407 /* Unless wanted raw, remove trailing whitespace, including the
1408 newline. */
1409
1410 if (!want_raw)
1411 while (ilen > 0 && isspace(t[ilen-1])) ilen--;
1412
059ec3d9
PH
1413 /* Set comma = 1 if handling a single header and it's one of those
1414 that contains an address list, except when asked for raw headers. Only
1415 need to do this once. */
1416
1417 if (!want_raw && name != NULL && comma == 0 &&
1418 Ustrchr("BCFRST", h->type) != NULL)
1419 comma = 1;
1420
1421 /* First pass - compute total store needed; second pass - compute
1422 total store used, including this header. */
1423
fd700877 1424 size += ilen + comma + 1; /* +1 for the newline */
059ec3d9
PH
1425
1426 /* Second pass - concatentate the data, up to a maximum. Note that
1427 the loop stops when size hits the limit. */
1428
1429 if (i != 0)
1430 {
1431 if (size > header_insert_maxlen)
1432 {
fd700877 1433 ilen -= size - header_insert_maxlen - 1;
059ec3d9
PH
1434 comma = 0;
1435 }
1436 Ustrncpy(ptr, t, ilen);
1437 ptr += ilen;
fd700877
PH
1438
1439 /* For a non-raw header, put in the comma if needed, then add
3168332a
PH
1440 back the newline we removed above, provided there was some text in
1441 the header. */
fd700877 1442
3168332a 1443 if (!want_raw && ilen > 0)
059ec3d9 1444 {
3168332a 1445 if (comma != 0) *ptr++ = ',';
059ec3d9
PH
1446 *ptr++ = '\n';
1447 }
1448 }
1449 }
1450 }
1451 }
1452
fd700877
PH
1453 /* At end of first pass, return NULL if no header found. Then truncate size
1454 if necessary, and get the buffer to hold the data, returning the buffer size.
1455 */
059ec3d9
PH
1456
1457 if (i == 0)
1458 {
1459 if (!found) return NULL;
1460 if (size > header_insert_maxlen) size = header_insert_maxlen;
1461 *newsize = size + 1;
1462 ptr = yield = store_get(*newsize);
1463 }
1464 }
1465
059ec3d9
PH
1466/* That's all we do for raw header expansion. */
1467
1468if (want_raw)
1469 {
1470 *ptr = 0;
1471 }
1472
fd700877
PH
1473/* Otherwise, remove a final newline and a redundant added comma. Then we do
1474RFC 2047 decoding, translating the charset if requested. The rfc2047_decode2()
059ec3d9
PH
1475function can return an error with decoded data if the charset translation
1476fails. If decoding fails, it returns NULL. */
1477
1478else
1479 {
1480 uschar *decoded, *error;
3168332a 1481 if (ptr > yield && ptr[-1] == '\n') ptr--;
fd700877 1482 if (ptr > yield && comma != 0 && ptr[-1] == ',') ptr--;
059ec3d9 1483 *ptr = 0;
a0d6ba8a
PH
1484 decoded = rfc2047_decode2(yield, check_rfc2047_length, charset, '?', NULL,
1485 newsize, &error);
059ec3d9
PH
1486 if (error != NULL)
1487 {
1488 DEBUG(D_any) debug_printf("*** error in RFC 2047 decoding: %s\n"
1489 " input was: %s\n", error, yield);
1490 }
1491 if (decoded != NULL) yield = decoded;
1492 }
1493
1494return yield;
1495}
1496
1497
1498
1499
1500/*************************************************
362145b5
JH
1501* Return list of recipients *
1502*************************************************/
1503/* A recipients list is available only during system message filtering,
1504during ACL processing after DATA, and while expanding pipe commands
1505generated from a system filter, but not elsewhere. */
1506
1507static uschar *
1508fn_recipients(void)
1509{
1510if (!enable_dollar_recipients) return NULL; else
1511 {
1512 int size = 128;
1513 int ptr = 0;
1514 int i;
1515 uschar * s = store_get(size);
1516 for (i = 0; i < recipients_count; i++)
1517 {
1518 if (i != 0) s = string_cat(s, &size, &ptr, US", ", 2);
1519 s = string_cat(s, &size, &ptr, recipients_list[i].address,
1520 Ustrlen(recipients_list[i].address));
1521 }
1522 s[ptr] = 0; /* string_cat() leaves room */
1523 return s;
1524 }
1525}
1526
1527
1528/*************************************************
059ec3d9
PH
1529* Find value of a variable *
1530*************************************************/
1531
1532/* The table of variables is kept in alphabetic order, so we can search it
1533using a binary chop. The "choplen" variable is nothing to do with the binary
1534chop.
1535
1536Arguments:
1537 name the name of the variable being sought
1538 exists_only TRUE if this is a def: test; passed on to find_header()
1539 skipping TRUE => skip any processing evaluation; this is not the same as
1540 exists_only because def: may test for values that are first
1541 evaluated here
1542 newsize pointer to an int which is initially zero; if the answer is in
1543 a new memory buffer, *newsize is set to its size
1544
1545Returns: NULL if the variable does not exist, or
1546 a pointer to the variable's contents, or
1547 something non-NULL if exists_only is TRUE
1548*/
1549
1550static uschar *
1551find_variable(uschar *name, BOOL exists_only, BOOL skipping, int *newsize)
1552{
1553int first = 0;
1554int last = var_table_size;
1555
38a0a95f
PH
1556/* Handle ACL variables, whose names are of the form acl_cxxx or acl_mxxx.
1557Originally, xxx had to be a number in the range 0-9 (later 0-19), but from
1558release 4.64 onwards arbitrary names are permitted, as long as the first 5
641cb756
PH
1559characters are acl_c or acl_m and the sixth is either a digit or an underscore
1560(this gave backwards compatibility at the changeover). There may be built-in
1561variables whose names start acl_ but they should never start in this way. This
1562slightly messy specification is a consequence of the history, needless to say.
47ca6d6c 1563
38a0a95f
PH
1564If an ACL variable does not exist, treat it as empty, unless strict_acl_vars is
1565set, in which case give an error. */
47ca6d6c 1566
641cb756
PH
1567if ((Ustrncmp(name, "acl_c", 5) == 0 || Ustrncmp(name, "acl_m", 5) == 0) &&
1568 !isalpha(name[5]))
38a0a95f
PH
1569 {
1570 tree_node *node =
1571 tree_search((name[4] == 'c')? acl_var_c : acl_var_m, name + 4);
1572 return (node == NULL)? (strict_acl_vars? NULL : US"") : node->data.ptr;
47ca6d6c
PH
1573 }
1574
38a0a95f 1575/* Handle $auth<n> variables. */
f78eb7c6
PH
1576
1577if (Ustrncmp(name, "auth", 4) == 0)
1578 {
1579 uschar *endptr;
1580 int n = Ustrtoul(name + 4, &endptr, 10);
1581 if (*endptr == 0 && n != 0 && n <= AUTH_VARS)
1582 return (auth_vars[n-1] == NULL)? US"" : auth_vars[n-1];
1583 }
1584
47ca6d6c
PH
1585/* For all other variables, search the table */
1586
059ec3d9
PH
1587while (last > first)
1588 {
1589 uschar *s, *domain;
1590 uschar **ss;
1591 int middle = (first + last)/2;
1592 int c = Ustrcmp(name, var_table[middle].name);
1593
1594 if (c > 0) { first = middle + 1; continue; }
1595 if (c < 0) { last = middle; continue; }
1596
1597 /* Found an existing variable. If in skipping state, the value isn't needed,
47ca6d6c 1598 and we want to avoid processing (such as looking up the host name). */
059ec3d9
PH
1599
1600 if (skipping) return US"";
1601
1602 switch (var_table[middle].type)
1603 {
9a26b6b2
PH
1604 case vtype_filter_int:
1605 if (!filter_running) return NULL;
1606 /* Fall through */
1607 /* VVVVVVVVVVVV */
059ec3d9
PH
1608 case vtype_int:
1609 sprintf(CS var_buffer, "%d", *(int *)(var_table[middle].value)); /* Integer */
1610 return var_buffer;
1611
1612 case vtype_ino:
1613 sprintf(CS var_buffer, "%ld", (long int)(*(ino_t *)(var_table[middle].value))); /* Inode */
1614 return var_buffer;
1615
1616 case vtype_gid:
1617 sprintf(CS var_buffer, "%ld", (long int)(*(gid_t *)(var_table[middle].value))); /* gid */
1618 return var_buffer;
1619
1620 case vtype_uid:
1621 sprintf(CS var_buffer, "%ld", (long int)(*(uid_t *)(var_table[middle].value))); /* uid */
1622 return var_buffer;
1623
11d7e4fa
PP
1624 case vtype_bool:
1625 sprintf(CS var_buffer, "%s", *(BOOL *)(var_table[middle].value) ? "yes" : "no"); /* bool */
1626 return var_buffer;
1627
059ec3d9
PH
1628 case vtype_stringptr: /* Pointer to string */
1629 s = *((uschar **)(var_table[middle].value));
1630 return (s == NULL)? US"" : s;
1631
1632 case vtype_pid:
1633 sprintf(CS var_buffer, "%d", (int)getpid()); /* pid */
1634 return var_buffer;
1635
1636 case vtype_load_avg:
8669f003 1637 sprintf(CS var_buffer, "%d", OS_GETLOADAVG()); /* load_average */
059ec3d9
PH
1638 return var_buffer;
1639
1640 case vtype_host_lookup: /* Lookup if not done so */
1641 if (sender_host_name == NULL && sender_host_address != NULL &&
1642 !host_lookup_failed && host_name_lookup() == OK)
1643 host_build_sender_fullhost();
1644 return (sender_host_name == NULL)? US"" : sender_host_name;
1645
1646 case vtype_localpart: /* Get local part from address */
1647 s = *((uschar **)(var_table[middle].value));
1648 if (s == NULL) return US"";
1649 domain = Ustrrchr(s, '@');
1650 if (domain == NULL) return s;
1651 if (domain - s > sizeof(var_buffer) - 1)
81f91683
PP
1652 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "local part longer than " SIZE_T_FMT
1653 " in string expansion", sizeof(var_buffer));
059ec3d9
PH
1654 Ustrncpy(var_buffer, s, domain - s);
1655 var_buffer[domain - s] = 0;
1656 return var_buffer;
1657
1658 case vtype_domain: /* Get domain from address */
1659 s = *((uschar **)(var_table[middle].value));
1660 if (s == NULL) return US"";
1661 domain = Ustrrchr(s, '@');
1662 return (domain == NULL)? US"" : domain + 1;
1663
1664 case vtype_msgheaders:
1665 return find_header(NULL, exists_only, newsize, FALSE, NULL);
1666
ff75a1f7
PH
1667 case vtype_msgheaders_raw:
1668 return find_header(NULL, exists_only, newsize, TRUE, NULL);
1669
059ec3d9
PH
1670 case vtype_msgbody: /* Pointer to msgbody string */
1671 case vtype_msgbody_end: /* Ditto, the end of the msg */
1672 ss = (uschar **)(var_table[middle].value);
1673 if (*ss == NULL && deliver_datafile >= 0) /* Read body when needed */
1674 {
1675 uschar *body;
0d7eb84a 1676 off_t start_offset = SPOOL_DATA_START_OFFSET;
059ec3d9
PH
1677 int len = message_body_visible;
1678 if (len > message_size) len = message_size;
1679 *ss = body = store_malloc(len+1);
1680 body[0] = 0;
1681 if (var_table[middle].type == vtype_msgbody_end)
1682 {
1683 struct stat statbuf;
1684 if (fstat(deliver_datafile, &statbuf) == 0)
1685 {
1686 start_offset = statbuf.st_size - len;
1687 if (start_offset < SPOOL_DATA_START_OFFSET)
1688 start_offset = SPOOL_DATA_START_OFFSET;
1689 }
1690 }
1691 lseek(deliver_datafile, start_offset, SEEK_SET);
1692 len = read(deliver_datafile, body, len);
1693 if (len > 0)
1694 {
1695 body[len] = 0;
ddea74fa 1696 if (message_body_newlines) /* Separate loops for efficiency */
059ec3d9 1697 {
ddea74fa
PH
1698 while (len > 0)
1699 { if (body[--len] == 0) body[len] = ' '; }
1700 }
1701 else
1702 {
1703 while (len > 0)
1704 { if (body[--len] == '\n' || body[len] == 0) body[len] = ' '; }
059ec3d9
PH
1705 }
1706 }
1707 }
1708 return (*ss == NULL)? US"" : *ss;
1709
1710 case vtype_todbsdin: /* BSD inbox time of day */
1711 return tod_stamp(tod_bsdin);
1712
1713 case vtype_tode: /* Unix epoch time of day */
1714 return tod_stamp(tod_epoch);
1715
f5787926
JH
1716 case vtype_todel: /* Unix epoch/usec time of day */
1717 return tod_stamp(tod_epoch_l);
1718
059ec3d9
PH
1719 case vtype_todf: /* Full time of day */
1720 return tod_stamp(tod_full);
1721
1722 case vtype_todl: /* Log format time of day */
1723 return tod_stamp(tod_log_bare); /* (without timezone) */
1724
1725 case vtype_todzone: /* Time zone offset only */
1726 return tod_stamp(tod_zone);
1727
1728 case vtype_todzulu: /* Zulu time */
1729 return tod_stamp(tod_zulu);
1730
1731 case vtype_todlf: /* Log file datestamp tod */
f1e5fef5 1732 return tod_stamp(tod_log_datestamp_daily);
059ec3d9
PH
1733
1734 case vtype_reply: /* Get reply address */
c8ea1597 1735 s = find_header(US"reply-to:", exists_only, newsize, TRUE,
059ec3d9 1736 headers_charset);
6979240a 1737 if (s != NULL) while (isspace(*s)) s++;
059ec3d9 1738 if (s == NULL || *s == 0)
41a13e0a
PH
1739 {
1740 *newsize = 0; /* For the *s==0 case */
c8ea1597
PH
1741 s = find_header(US"from:", exists_only, newsize, TRUE, headers_charset);
1742 }
1743 if (s != NULL)
1744 {
1745 uschar *t;
1746 while (isspace(*s)) s++;
1747 for (t = s; *t != 0; t++) if (*t == '\n') *t = ' ';
6979240a
PH
1748 while (t > s && isspace(t[-1])) t--;
1749 *t = 0;
41a13e0a 1750 }
059ec3d9
PH
1751 return (s == NULL)? US"" : s;
1752
362145b5 1753 case vtype_string_func:
059ec3d9 1754 {
362145b5
JH
1755 uschar * (*fn)() = var_table[middle].value;
1756 return fn();
059ec3d9 1757 }
8e669ac1 1758
5cb8cbc6
PH
1759 case vtype_pspace:
1760 {
1761 int inodes;
8e669ac1
PH
1762 sprintf(CS var_buffer, "%d",
1763 receive_statvfs(var_table[middle].value == (void *)TRUE, &inodes));
5cb8cbc6
PH
1764 }
1765 return var_buffer;
8e669ac1 1766
5cb8cbc6
PH
1767 case vtype_pinodes:
1768 {
1769 int inodes;
8e669ac1 1770 (void) receive_statvfs(var_table[middle].value == (void *)TRUE, &inodes);
5cb8cbc6
PH
1771 sprintf(CS var_buffer, "%d", inodes);
1772 }
1773 return var_buffer;
80a47a2c 1774
c8307c12 1775 #ifndef DISABLE_DKIM
80a47a2c 1776 case vtype_dkim:
da5dfc3a 1777 return dkim_exim_expand_query((int)(long)var_table[middle].value);
80a47a2c
TK
1778 #endif
1779
059ec3d9
PH
1780 }
1781 }
1782
1783return NULL; /* Unknown variable name */
1784}
1785
1786
1787
1788
d9b2312b
JH
1789void
1790modify_variable(uschar *name, void * value)
1791{
1792int first = 0;
1793int last = var_table_size;
1794
1795while (last > first)
1796 {
1797 int middle = (first + last)/2;
1798 int c = Ustrcmp(name, var_table[middle].name);
1799
1800 if (c > 0) { first = middle + 1; continue; }
1801 if (c < 0) { last = middle; continue; }
1802
1803 /* Found an existing variable; change the item it refers to */
1804 var_table[middle].value = value;
1805 return;
1806 }
1807return; /* Unknown variable name, fail silently */
1808}
1809
1810
1811
1812
1813
059ec3d9
PH
1814/*************************************************
1815* Read and expand substrings *
1816*************************************************/
1817
1818/* This function is called to read and expand argument substrings for various
1819expansion items. Some have a minimum requirement that is less than the maximum;
1820in these cases, the first non-present one is set to NULL.
1821
1822Arguments:
1823 sub points to vector of pointers to set
1824 n maximum number of substrings
1825 m minimum required
1826 sptr points to current string pointer
1827 skipping the skipping flag
1828 check_end if TRUE, check for final '}'
1829 name name of item, for error message
b0e85a8f
JH
1830 resetok if not NULL, pointer to flag - write FALSE if unsafe to reset
1831 the store.
059ec3d9
PH
1832
1833Returns: 0 OK; string pointer updated
1834 1 curly bracketing error (too few arguments)
1835 2 too many arguments (only if check_end is set); message set
1836 3 other error (expansion failure)
1837*/
1838
1839static int
1840read_subs(uschar **sub, int n, int m, uschar **sptr, BOOL skipping,
b0e85a8f 1841 BOOL check_end, uschar *name, BOOL *resetok)
059ec3d9
PH
1842{
1843int i;
1844uschar *s = *sptr;
1845
1846while (isspace(*s)) s++;
1847for (i = 0; i < n; i++)
1848 {
1849 if (*s != '{')
1850 {
1851 if (i < m) return 1;
1852 sub[i] = NULL;
1853 break;
1854 }
b0e85a8f 1855 sub[i] = expand_string_internal(s+1, TRUE, &s, skipping, TRUE, resetok);
059ec3d9
PH
1856 if (sub[i] == NULL) return 3;
1857 if (*s++ != '}') return 1;
1858 while (isspace(*s)) s++;
1859 }
1860if (check_end && *s++ != '}')
1861 {
1862 if (s[-1] == '{')
1863 {
1864 expand_string_message = string_sprintf("Too many arguments for \"%s\" "
1865 "(max is %d)", name, n);
1866 return 2;
1867 }
1868 return 1;
1869 }
1870
1871*sptr = s;
1872return 0;
1873}
1874
1875
1876
1877
1878/*************************************************
641cb756
PH
1879* Elaborate message for bad variable *
1880*************************************************/
1881
1882/* For the "unknown variable" message, take a look at the variable's name, and
1883give additional information about possible ACL variables. The extra information
1884is added on to expand_string_message.
1885
1886Argument: the name of the variable
1887Returns: nothing
1888*/
1889
1890static void
1891check_variable_error_message(uschar *name)
1892{
1893if (Ustrncmp(name, "acl_", 4) == 0)
1894 expand_string_message = string_sprintf("%s (%s)", expand_string_message,
1895 (name[4] == 'c' || name[4] == 'm')?
1896 (isalpha(name[5])?
1897 US"6th character of a user-defined ACL variable must be a digit or underscore" :
1898 US"strict_acl_vars is set" /* Syntax is OK, it has to be this */
1899 ) :
1900 US"user-defined ACL variables must start acl_c or acl_m");
1901}
1902
1903
1904
f60d98e8
JH
1905/*
1906Load args from sub array to globals, and call acl_check().
ef21c07d 1907Sub array will be corrupted on return.
f60d98e8
JH
1908
1909Returns: OK access is granted by an ACCEPT verb
1910 DISCARD access is granted by a DISCARD verb
1911 FAIL access is denied
1912 FAIL_DROP access is denied; drop the connection
1913 DEFER can't tell at the moment
1914 ERROR disaster
1915*/
1916static int
1917eval_acl(uschar ** sub, int nsub, uschar ** user_msgp)
1918{
1919int i;
ef21c07d
JH
1920uschar *tmp;
1921int sav_narg = acl_narg;
1922int ret;
faa05a93 1923extern int acl_where;
f60d98e8 1924
ef21c07d
JH
1925if(--nsub > sizeof(acl_arg)/sizeof(*acl_arg)) nsub = sizeof(acl_arg)/sizeof(*acl_arg);
1926for (i = 0; i < nsub && sub[i+1]; i++)
1927 {
1928 tmp = acl_arg[i];
1929 acl_arg[i] = sub[i+1]; /* place callers args in the globals */
1930 sub[i+1] = tmp; /* stash the old args using our caller's storage */
1931 }
1932acl_narg = i;
bef3ea7f 1933while (i < nsub)
ef21c07d
JH
1934 {
1935 sub[i+1] = acl_arg[i];
1936 acl_arg[i++] = NULL;
1937 }
f60d98e8
JH
1938
1939DEBUG(D_expand)
1940 debug_printf("expanding: acl: %s arg: %s%s\n",
1941 sub[0],
60f8e1e8
JH
1942 acl_narg>0 ? acl_arg[0] : US"<none>",
1943 acl_narg>1 ? " +more" : "");
f60d98e8 1944
05caaeaa 1945ret = acl_eval(acl_where, sub[0], user_msgp, &tmp);
ef21c07d
JH
1946
1947for (i = 0; i < nsub; i++)
1948 acl_arg[i] = sub[i+1]; /* restore old args */
1949acl_narg = sav_narg;
1950
1951return ret;
f60d98e8
JH
1952}
1953
1954
1955
1956
641cb756 1957/*************************************************
059ec3d9
PH
1958* Read and evaluate a condition *
1959*************************************************/
1960
1961/*
1962Arguments:
1963 s points to the start of the condition text
b0e85a8f
JH
1964 resetok points to a BOOL which is written false if it is unsafe to
1965 free memory. Certain condition types (acl) may have side-effect
1966 allocation which must be preserved.
059ec3d9
PH
1967 yield points to a BOOL to hold the result of the condition test;
1968 if NULL, we are just reading through a condition that is
1969 part of an "or" combination to check syntax, or in a state
1970 where the answer isn't required
1971
1972Returns: a pointer to the first character after the condition, or
1973 NULL after an error
1974*/
1975
1976static uschar *
b0e85a8f 1977eval_condition(uschar *s, BOOL *resetok, BOOL *yield)
059ec3d9
PH
1978{
1979BOOL testfor = TRUE;
1980BOOL tempcond, combined_cond;
1981BOOL *subcondptr;
5cfd2e57 1982BOOL sub2_honour_dollar = TRUE;
059ec3d9 1983int i, rc, cond_type, roffset;
97d17305 1984int_eximarith_t num[2];
059ec3d9
PH
1985struct stat statbuf;
1986uschar name[256];
f60d98e8 1987uschar *sub[10];
059ec3d9
PH
1988
1989const pcre *re;
1990const uschar *rerror;
1991
1992for (;;)
1993 {
1994 while (isspace(*s)) s++;
1995 if (*s == '!') { testfor = !testfor; s++; } else break;
1996 }
1997
1998/* Numeric comparisons are symbolic */
1999
2000if (*s == '=' || *s == '>' || *s == '<')
2001 {
2002 int p = 0;
2003 name[p++] = *s++;
2004 if (*s == '=')
2005 {
2006 name[p++] = '=';
2007 s++;
2008 }
2009 name[p] = 0;
2010 }
2011
2012/* All other conditions are named */
2013
2014else s = read_name(name, 256, s, US"_");
2015
2016/* If we haven't read a name, it means some non-alpha character is first. */
2017
2018if (name[0] == 0)
2019 {
2020 expand_string_message = string_sprintf("condition name expected, "
2021 "but found \"%.16s\"", s);
2022 return NULL;
2023 }
2024
2025/* Find which condition we are dealing with, and switch on it */
2026
2027cond_type = chop_match(name, cond_table, sizeof(cond_table)/sizeof(uschar *));
2028switch(cond_type)
2029 {
9b4768fa
PH
2030 /* def: tests for a non-empty variable, or for the existence of a header. If
2031 yield == NULL we are in a skipping state, and don't care about the answer. */
059ec3d9
PH
2032
2033 case ECOND_DEF:
2034 if (*s != ':')
2035 {
2036 expand_string_message = US"\":\" expected after \"def\"";
2037 return NULL;
2038 }
2039
2040 s = read_name(name, 256, s+1, US"_");
2041
0d85fa3f
PH
2042 /* Test for a header's existence. If the name contains a closing brace
2043 character, this may be a user error where the terminating colon has been
2044 omitted. Set a flag to adjust a subsequent error message in this case. */
059ec3d9
PH
2045
2046 if (Ustrncmp(name, "h_", 2) == 0 ||
2047 Ustrncmp(name, "rh_", 3) == 0 ||
2048 Ustrncmp(name, "bh_", 3) == 0 ||
2049 Ustrncmp(name, "header_", 7) == 0 ||
2050 Ustrncmp(name, "rheader_", 8) == 0 ||
2051 Ustrncmp(name, "bheader_", 8) == 0)
2052 {
2053 s = read_header_name(name, 256, s);
b5b871ac 2054 /* {-for-text-editors */
0d85fa3f 2055 if (Ustrchr(name, '}') != NULL) malformed_header = TRUE;
059ec3d9
PH
2056 if (yield != NULL) *yield =
2057 (find_header(name, TRUE, NULL, FALSE, NULL) != NULL) == testfor;
2058 }
2059
9b4768fa
PH
2060 /* Test for a variable's having a non-empty value. A non-existent variable
2061 causes an expansion failure. */
059ec3d9
PH
2062
2063 else
2064 {
2065 uschar *value = find_variable(name, TRUE, yield == NULL, NULL);
2066 if (value == NULL)
2067 {
2068 expand_string_message = (name[0] == 0)?
2069 string_sprintf("variable name omitted after \"def:\"") :
2070 string_sprintf("unknown variable \"%s\" after \"def:\"", name);
641cb756 2071 check_variable_error_message(name);
059ec3d9
PH
2072 return NULL;
2073 }
9b4768fa 2074 if (yield != NULL) *yield = (value[0] != 0) == testfor;
059ec3d9
PH
2075 }
2076
2077 return s;
2078
2079
2080 /* first_delivery tests for first delivery attempt */
2081
2082 case ECOND_FIRST_DELIVERY:
2083 if (yield != NULL) *yield = deliver_firsttime == testfor;
2084 return s;
2085
2086
2087 /* queue_running tests for any process started by a queue runner */
2088
2089 case ECOND_QUEUE_RUNNING:
2090 if (yield != NULL) *yield = (queue_run_pid != (pid_t)0) == testfor;
2091 return s;
2092
2093
2094 /* exists: tests for file existence
2095 isip: tests for any IP address
2096 isip4: tests for an IPv4 address
2097 isip6: tests for an IPv6 address
2098 pam: does PAM authentication
2099 radius: does RADIUS authentication
2100 ldapauth: does LDAP authentication
2101 pwcheck: does Cyrus SASL pwcheck authentication
2102 */
2103
2104 case ECOND_EXISTS:
2105 case ECOND_ISIP:
2106 case ECOND_ISIP4:
2107 case ECOND_ISIP6:
2108 case ECOND_PAM:
2109 case ECOND_RADIUS:
2110 case ECOND_LDAPAUTH:
2111 case ECOND_PWCHECK:
2112
2113 while (isspace(*s)) s++;
b5b871ac 2114 if (*s != '{') goto COND_FAILED_CURLY_START; /* }-for-text-editors */
059ec3d9 2115
b0e85a8f 2116 sub[0] = expand_string_internal(s+1, TRUE, &s, yield == NULL, TRUE, resetok);
059ec3d9 2117 if (sub[0] == NULL) return NULL;
b5b871ac 2118 /* {-for-text-editors */
059ec3d9
PH
2119 if (*s++ != '}') goto COND_FAILED_CURLY_END;
2120
2121 if (yield == NULL) return s; /* No need to run the test if skipping */
2122
2123 switch(cond_type)
2124 {
2125 case ECOND_EXISTS:
2126 if ((expand_forbid & RDO_EXISTS) != 0)
2127 {
2128 expand_string_message = US"File existence tests are not permitted";
2129 return NULL;
2130 }
2131 *yield = (Ustat(sub[0], &statbuf) == 0) == testfor;
2132 break;
2133
2134 case ECOND_ISIP:
2135 case ECOND_ISIP4:
2136 case ECOND_ISIP6:
2137 rc = string_is_ip_address(sub[0], NULL);
7e66e54d 2138 *yield = ((cond_type == ECOND_ISIP)? (rc != 0) :
059ec3d9
PH
2139 (cond_type == ECOND_ISIP4)? (rc == 4) : (rc == 6)) == testfor;
2140 break;
2141
2142 /* Various authentication tests - all optionally compiled */
2143
2144 case ECOND_PAM:
2145 #ifdef SUPPORT_PAM
2146 rc = auth_call_pam(sub[0], &expand_string_message);
2147 goto END_AUTH;
2148 #else
2149 goto COND_FAILED_NOT_COMPILED;
2150 #endif /* SUPPORT_PAM */
2151
2152 case ECOND_RADIUS:
2153 #ifdef RADIUS_CONFIG_FILE
2154 rc = auth_call_radius(sub[0], &expand_string_message);
2155 goto END_AUTH;
2156 #else
2157 goto COND_FAILED_NOT_COMPILED;
2158 #endif /* RADIUS_CONFIG_FILE */
2159
2160 case ECOND_LDAPAUTH:
2161 #ifdef LOOKUP_LDAP
2162 {
2163 /* Just to keep the interface the same */
2164 BOOL do_cache;
2165 int old_pool = store_pool;
2166 store_pool = POOL_SEARCH;
2167 rc = eldapauth_find((void *)(-1), NULL, sub[0], Ustrlen(sub[0]), NULL,
2168 &expand_string_message, &do_cache);
2169 store_pool = old_pool;
2170 }
2171 goto END_AUTH;
2172 #else
2173 goto COND_FAILED_NOT_COMPILED;
2174 #endif /* LOOKUP_LDAP */
2175
2176 case ECOND_PWCHECK:
2177 #ifdef CYRUS_PWCHECK_SOCKET
2178 rc = auth_call_pwcheck(sub[0], &expand_string_message);
2179 goto END_AUTH;
2180 #else
2181 goto COND_FAILED_NOT_COMPILED;
2182 #endif /* CYRUS_PWCHECK_SOCKET */
2183
2184 #if defined(SUPPORT_PAM) || defined(RADIUS_CONFIG_FILE) || \
2185 defined(LOOKUP_LDAP) || defined(CYRUS_PWCHECK_SOCKET)
2186 END_AUTH:
2187 if (rc == ERROR || rc == DEFER) return NULL;
2188 *yield = (rc == OK) == testfor;
2189 #endif
2190 }
2191 return s;
2192
2193
333eea9c
JH
2194 /* call ACL (in a conditional context). Accept true, deny false.
2195 Defer is a forced-fail. Anything set by message= goes to $value.
f60d98e8
JH
2196 Up to ten parameters are used; we use the braces round the name+args
2197 like the saslauthd condition does, to permit a variable number of args.
2198 See also the expansion-item version EITEM_ACL and the traditional
2199 acl modifier ACLC_ACL.
fd5dad68
JH
2200 Since the ACL may allocate new global variables, tell our caller to not
2201 reclaim memory.
f60d98e8 2202 */
333eea9c
JH
2203
2204 case ECOND_ACL:
bef3ea7f 2205 /* ${if acl {{name}{arg1}{arg2}...} {yes}{no}} */
333eea9c 2206 {
333eea9c 2207 uschar *user_msg;
333eea9c 2208 BOOL cond = FALSE;
bef3ea7f
JH
2209 int size = 0;
2210 int ptr = 0;
333eea9c
JH
2211
2212 while (isspace(*s)) s++;
6d9cfc47 2213 if (*s++ != '{') goto COND_FAILED_CURLY_START; /*}*/
333eea9c 2214
f60d98e8 2215 switch(read_subs(sub, sizeof(sub)/sizeof(*sub), 1,
b0e85a8f 2216 &s, yield == NULL, TRUE, US"acl", resetok))
333eea9c 2217 {
f60d98e8
JH
2218 case 1: expand_string_message = US"too few arguments or bracketing "
2219 "error for acl";
2220 case 2:
2221 case 3: return NULL;
333eea9c 2222 }
f60d98e8 2223
b0e85a8f 2224 *resetok = FALSE;
bef3ea7f 2225 if (yield != NULL) switch(eval_acl(sub, sizeof(sub)/sizeof(*sub), &user_msg))
f60d98e8
JH
2226 {
2227 case OK:
2228 cond = TRUE;
2229 case FAIL:
bef3ea7f 2230 lookup_value = NULL;
f60d98e8 2231 if (user_msg)
bef3ea7f 2232 {
f60d98e8 2233 lookup_value = string_cat(NULL, &size, &ptr, user_msg, Ustrlen(user_msg));
bef3ea7f
JH
2234 lookup_value[ptr] = '\0';
2235 }
b5b871ac 2236 *yield = cond == testfor;
f60d98e8
JH
2237 break;
2238
2239 case DEFER:
2240 expand_string_forcedfail = TRUE;
2241 default:
2242 expand_string_message = string_sprintf("error from acl \"%s\"", sub[0]);
2243 return NULL;
2244 }
2245 return s;
333eea9c 2246 }
333eea9c
JH
2247
2248
059ec3d9
PH
2249 /* saslauthd: does Cyrus saslauthd authentication. Four parameters are used:
2250
b0e85a8f 2251 ${if saslauthd {{username}{password}{service}{realm}} {yes}{no}}
059ec3d9
PH
2252
2253 However, the last two are optional. That is why the whole set is enclosed
333eea9c 2254 in their own set of braces. */
059ec3d9
PH
2255
2256 case ECOND_SASLAUTHD:
2257 #ifndef CYRUS_SASLAUTHD_SOCKET
2258 goto COND_FAILED_NOT_COMPILED;
2259 #else
2260 while (isspace(*s)) s++;
b5b871ac 2261 if (*s++ != '{') goto COND_FAILED_CURLY_START; /* }-for-text-editors */
b0e85a8f 2262 switch(read_subs(sub, 4, 2, &s, yield == NULL, TRUE, US"saslauthd", resetok))
059ec3d9
PH
2263 {
2264 case 1: expand_string_message = US"too few arguments or bracketing "
2265 "error for saslauthd";
2266 case 2:
2267 case 3: return NULL;
2268 }
2269 if (sub[2] == NULL) sub[3] = NULL; /* realm if no service */
2270 if (yield != NULL)
2271 {
2272 int rc;
2273 rc = auth_call_saslauthd(sub[0], sub[1], sub[2], sub[3],
2274 &expand_string_message);
2275 if (rc == ERROR || rc == DEFER) return NULL;
2276 *yield = (rc == OK) == testfor;
2277 }
2278 return s;
2279 #endif /* CYRUS_SASLAUTHD_SOCKET */
2280
2281
2282 /* symbolic operators for numeric and string comparison, and a number of
2283 other operators, all requiring two arguments.
2284
76dca828
PP
2285 crypteq: encrypts plaintext and compares against an encrypted text,
2286 using crypt(), crypt16(), MD5 or SHA-1
2287 inlist/inlisti: checks if first argument is in the list of the second
059ec3d9
PH
2288 match: does a regular expression match and sets up the numerical
2289 variables if it succeeds
2290 match_address: matches in an address list
2291 match_domain: matches in a domain list
32d668a5 2292 match_ip: matches a host list that is restricted to IP addresses
059ec3d9 2293 match_local_part: matches in a local part list
059ec3d9
PH
2294 */
2295
059ec3d9
PH
2296 case ECOND_MATCH_ADDRESS:
2297 case ECOND_MATCH_DOMAIN:
32d668a5 2298 case ECOND_MATCH_IP:
059ec3d9 2299 case ECOND_MATCH_LOCAL_PART:
da6dbe26
PP
2300#ifndef EXPAND_LISTMATCH_RHS
2301 sub2_honour_dollar = FALSE;
2302#endif
2303 /* FALLTHROUGH */
2304
2305 case ECOND_CRYPTEQ:
2306 case ECOND_INLIST:
2307 case ECOND_INLISTI:
2308 case ECOND_MATCH:
059ec3d9
PH
2309
2310 case ECOND_NUM_L: /* Numerical comparisons */
2311 case ECOND_NUM_LE:
2312 case ECOND_NUM_E:
2313 case ECOND_NUM_EE:
2314 case ECOND_NUM_G:
2315 case ECOND_NUM_GE:
2316
2317 case ECOND_STR_LT: /* String comparisons */
2318 case ECOND_STR_LTI:
2319 case ECOND_STR_LE:
2320 case ECOND_STR_LEI:
2321 case ECOND_STR_EQ:
2322 case ECOND_STR_EQI:
2323 case ECOND_STR_GT:
2324 case ECOND_STR_GTI:
2325 case ECOND_STR_GE:
2326 case ECOND_STR_GEI:
2327
2328 for (i = 0; i < 2; i++)
2329 {
da6dbe26
PP
2330 /* Sometimes, we don't expand substrings; too many insecure configurations
2331 created using match_address{}{} and friends, where the second param
2332 includes information from untrustworthy sources. */
2333 BOOL honour_dollar = TRUE;
2334 if ((i > 0) && !sub2_honour_dollar)
2335 honour_dollar = FALSE;
2336
059ec3d9
PH
2337 while (isspace(*s)) s++;
2338 if (*s != '{')
2339 {
2340 if (i == 0) goto COND_FAILED_CURLY_START;
2341 expand_string_message = string_sprintf("missing 2nd string in {} "
2342 "after \"%s\"", name);
2343 return NULL;
2344 }
da6dbe26 2345 sub[i] = expand_string_internal(s+1, TRUE, &s, yield == NULL,
b0e85a8f 2346 honour_dollar, resetok);
059ec3d9
PH
2347 if (sub[i] == NULL) return NULL;
2348 if (*s++ != '}') goto COND_FAILED_CURLY_END;
2349
2350 /* Convert to numerical if required; we know that the names of all the
2351 conditions that compare numbers do not start with a letter. This just saves
2352 checking for them individually. */
2353
d6066548 2354 if (!isalpha(name[0]) && yield != NULL)
059ec3d9 2355 {
5dd1517f
PH
2356 if (sub[i][0] == 0)
2357 {
2358 num[i] = 0;
2359 DEBUG(D_expand)
2360 debug_printf("empty string cast to zero for numerical comparison\n");
2361 }
2362 else
2363 {
2364 num[i] = expand_string_integer(sub[i], FALSE);
2365 if (expand_string_message != NULL) return NULL;
2366 }
059ec3d9
PH
2367 }
2368 }
2369
2370 /* Result not required */
2371
2372 if (yield == NULL) return s;
2373
2374 /* Do an appropriate comparison */
2375
2376 switch(cond_type)
2377 {
2378 case ECOND_NUM_E:
2379 case ECOND_NUM_EE:
b5b871ac 2380 tempcond = (num[0] == num[1]);
059ec3d9
PH
2381 break;
2382
2383 case ECOND_NUM_G:
b5b871ac 2384 tempcond = (num[0] > num[1]);
059ec3d9
PH
2385 break;
2386
2387 case ECOND_NUM_GE:
b5b871ac 2388 tempcond = (num[0] >= num[1]);
059ec3d9
PH
2389 break;
2390
2391 case ECOND_NUM_L:
b5b871ac 2392 tempcond = (num[0] < num[1]);
059ec3d9
PH
2393 break;
2394
2395 case ECOND_NUM_LE:
b5b871ac 2396 tempcond = (num[0] <= num[1]);
059ec3d9
PH
2397 break;
2398
2399 case ECOND_STR_LT:
b5b871ac 2400 tempcond = (Ustrcmp(sub[0], sub[1]) < 0);
059ec3d9
PH
2401 break;
2402
2403 case ECOND_STR_LTI:
b5b871ac 2404 tempcond = (strcmpic(sub[0], sub[1]) < 0);
059ec3d9
PH
2405 break;
2406
2407 case ECOND_STR_LE:
b5b871ac 2408 tempcond = (Ustrcmp(sub[0], sub[1]) <= 0);
059ec3d9
PH
2409 break;
2410
2411 case ECOND_STR_LEI:
b5b871ac 2412 tempcond = (strcmpic(sub[0], sub[1]) <= 0);
059ec3d9
PH
2413 break;
2414
2415 case ECOND_STR_EQ:
b5b871ac 2416 tempcond = (Ustrcmp(sub[0], sub[1]) == 0);
059ec3d9
PH
2417 break;
2418
2419 case ECOND_STR_EQI:
b5b871ac 2420 tempcond = (strcmpic(sub[0], sub[1]) == 0);
059ec3d9
PH
2421 break;
2422
2423 case ECOND_STR_GT:
b5b871ac 2424 tempcond = (Ustrcmp(sub[0], sub[1]) > 0);
059ec3d9
PH
2425 break;
2426
2427 case ECOND_STR_GTI:
b5b871ac 2428 tempcond = (strcmpic(sub[0], sub[1]) > 0);
059ec3d9
PH
2429 break;
2430
2431 case ECOND_STR_GE:
b5b871ac 2432 tempcond = (Ustrcmp(sub[0], sub[1]) >= 0);
059ec3d9
PH
2433 break;
2434
2435 case ECOND_STR_GEI:
b5b871ac 2436 tempcond = (strcmpic(sub[0], sub[1]) >= 0);
059ec3d9
PH
2437 break;
2438
2439 case ECOND_MATCH: /* Regular expression match */
2440 re = pcre_compile(CS sub[1], PCRE_COPT, (const char **)&rerror, &roffset,
2441 NULL);
2442 if (re == NULL)
2443 {
2444 expand_string_message = string_sprintf("regular expression error in "
2445 "\"%s\": %s at offset %d", sub[1], rerror, roffset);
2446 return NULL;
2447 }
b5b871ac 2448 tempcond = regex_match_and_setup(re, sub[0], 0, -1);
059ec3d9
PH
2449 break;
2450
2451 case ECOND_MATCH_ADDRESS: /* Match in an address list */
2452 rc = match_address_list(sub[0], TRUE, FALSE, &(sub[1]), NULL, -1, 0, NULL);
2453 goto MATCHED_SOMETHING;
2454
2455 case ECOND_MATCH_DOMAIN: /* Match in a domain list */
2456 rc = match_isinlist(sub[0], &(sub[1]), 0, &domainlist_anchor, NULL,
2457 MCL_DOMAIN + MCL_NOEXPAND, TRUE, NULL);
2458 goto MATCHED_SOMETHING;
2459
32d668a5 2460 case ECOND_MATCH_IP: /* Match IP address in a host list */
7e66e54d 2461 if (sub[0][0] != 0 && string_is_ip_address(sub[0], NULL) == 0)
32d668a5
PH
2462 {
2463 expand_string_message = string_sprintf("\"%s\" is not an IP address",
2464 sub[0]);
2465 return NULL;
2466 }
2467 else
2468 {
2469 unsigned int *nullcache = NULL;
2470 check_host_block cb;
2471
2472 cb.host_name = US"";
2473 cb.host_address = sub[0];
2474
2475 /* If the host address starts off ::ffff: it is an IPv6 address in
2476 IPv4-compatible mode. Find the IPv4 part for checking against IPv4
2477 addresses. */
2478
2479 cb.host_ipv4 = (Ustrncmp(cb.host_address, "::ffff:", 7) == 0)?
2480 cb.host_address + 7 : cb.host_address;
2481
2482 rc = match_check_list(
2483 &sub[1], /* the list */
2484 0, /* separator character */
2485 &hostlist_anchor, /* anchor pointer */
2486 &nullcache, /* cache pointer */
2487 check_host, /* function for testing */
2488 &cb, /* argument for function */
2489 MCL_HOST, /* type of check */
2490 sub[0], /* text for debugging */
2491 NULL); /* where to pass back data */
2492 }
2493 goto MATCHED_SOMETHING;
2494
059ec3d9
PH
2495 case ECOND_MATCH_LOCAL_PART:
2496 rc = match_isinlist(sub[0], &(sub[1]), 0, &localpartlist_anchor, NULL,
2497 MCL_LOCALPART + MCL_NOEXPAND, TRUE, NULL);
2498 /* Fall through */
9a26b6b2 2499 /* VVVVVVVVVVVV */
059ec3d9
PH
2500 MATCHED_SOMETHING:
2501 switch(rc)
2502 {
2503 case OK:
b5b871ac 2504 tempcond = TRUE;
059ec3d9
PH
2505 break;
2506
2507 case FAIL:
b5b871ac 2508 tempcond = FALSE;
059ec3d9
PH
2509 break;
2510
2511 case DEFER:
2512 expand_string_message = string_sprintf("unable to complete match "
2513 "against \"%s\": %s", sub[1], search_error_message);
2514 return NULL;
2515 }
2516
2517 break;
2518
2519 /* Various "encrypted" comparisons. If the second string starts with
2520 "{" then an encryption type is given. Default to crypt() or crypt16()
2521 (build-time choice). */
b5b871ac 2522 /* }-for-text-editors */
059ec3d9
PH
2523
2524 case ECOND_CRYPTEQ:
2525 #ifndef SUPPORT_CRYPTEQ
2526 goto COND_FAILED_NOT_COMPILED;
2527 #else
2528 if (strncmpic(sub[1], US"{md5}", 5) == 0)
2529 {
2530 int sublen = Ustrlen(sub[1]+5);
2531 md5 base;
2532 uschar digest[16];
2533
2534 md5_start(&base);
2535 md5_end(&base, (uschar *)sub[0], Ustrlen(sub[0]), digest);
2536
2537 /* If the length that we are comparing against is 24, the MD5 digest
2538 is expressed as a base64 string. This is the way LDAP does it. However,
2539 some other software uses a straightforward hex representation. We assume
2540 this if the length is 32. Other lengths fail. */
2541
2542 if (sublen == 24)
2543 {
2544 uschar *coded = auth_b64encode((uschar *)digest, 16);
2545 DEBUG(D_auth) debug_printf("crypteq: using MD5+B64 hashing\n"
2546 " subject=%s\n crypted=%s\n", coded, sub[1]+5);
b5b871ac 2547 tempcond = (Ustrcmp(coded, sub[1]+5) == 0);
059ec3d9
PH
2548 }
2549 else if (sublen == 32)
2550 {
2551 int i;
2552 uschar coded[36];
2553 for (i = 0; i < 16; i++) sprintf(CS (coded+2*i), "%02X", digest[i]);
2554 coded[32] = 0;
2555 DEBUG(D_auth) debug_printf("crypteq: using MD5+hex hashing\n"
2556 " subject=%s\n crypted=%s\n", coded, sub[1]+5);
b5b871ac 2557 tempcond = (strcmpic(coded, sub[1]+5) == 0);
059ec3d9
PH
2558 }
2559 else
2560 {
2561 DEBUG(D_auth) debug_printf("crypteq: length for MD5 not 24 or 32: "
2562 "fail\n crypted=%s\n", sub[1]+5);
b5b871ac 2563 tempcond = FALSE;
059ec3d9
PH
2564 }
2565 }
2566
2567 else if (strncmpic(sub[1], US"{sha1}", 6) == 0)
2568 {
2569 int sublen = Ustrlen(sub[1]+6);
2570 sha1 base;
2571 uschar digest[20];
2572
2573 sha1_start(&base);
2574 sha1_end(&base, (uschar *)sub[0], Ustrlen(sub[0]), digest);
2575
2576 /* If the length that we are comparing against is 28, assume the SHA1
2577 digest is expressed as a base64 string. If the length is 40, assume a
2578 straightforward hex representation. Other lengths fail. */
2579
2580 if (sublen == 28)
2581 {
2582 uschar *coded = auth_b64encode((uschar *)digest, 20);
2583 DEBUG(D_auth) debug_printf("crypteq: using SHA1+B64 hashing\n"
2584 " subject=%s\n crypted=%s\n", coded, sub[1]+6);
b5b871ac 2585 tempcond = (Ustrcmp(coded, sub[1]+6) == 0);
059ec3d9
PH
2586 }
2587 else if (sublen == 40)
2588 {
2589 int i;
2590 uschar coded[44];
2591 for (i = 0; i < 20; i++) sprintf(CS (coded+2*i), "%02X", digest[i]);
2592 coded[40] = 0;
2593 DEBUG(D_auth) debug_printf("crypteq: using SHA1+hex hashing\n"
2594 " subject=%s\n crypted=%s\n", coded, sub[1]+6);
b5b871ac 2595 tempcond = (strcmpic(coded, sub[1]+6) == 0);
059ec3d9
PH
2596 }
2597 else
2598 {
2599 DEBUG(D_auth) debug_printf("crypteq: length for SHA-1 not 28 or 40: "
2600 "fail\n crypted=%s\n", sub[1]+6);
b5b871ac 2601 tempcond = FALSE;
059ec3d9
PH
2602 }
2603 }
2604
2605 else /* {crypt} or {crypt16} and non-{ at start */
76dca828 2606 /* }-for-text-editors */
059ec3d9
PH
2607 {
2608 int which = 0;
2609 uschar *coded;
2610
2611 if (strncmpic(sub[1], US"{crypt}", 7) == 0)
2612 {
2613 sub[1] += 7;
2614 which = 1;
2615 }
2616 else if (strncmpic(sub[1], US"{crypt16}", 9) == 0)
2617 {
2618 sub[1] += 9;
2619 which = 2;
2620 }
b5b871ac 2621 else if (sub[1][0] == '{') /* }-for-text-editors */
059ec3d9
PH
2622 {
2623 expand_string_message = string_sprintf("unknown encryption mechanism "
2624 "in \"%s\"", sub[1]);
2625 return NULL;
2626 }
2627
2628 switch(which)
2629 {
2630 case 0: coded = US DEFAULT_CRYPT(CS sub[0], CS sub[1]); break;
2631 case 1: coded = US crypt(CS sub[0], CS sub[1]); break;
2632 default: coded = US crypt16(CS sub[0], CS sub[1]); break;
2633 }
2634
2635 #define STR(s) # s
2636 #define XSTR(s) STR(s)
2637 DEBUG(D_auth) debug_printf("crypteq: using %s()\n"
2638 " subject=%s\n crypted=%s\n",
2639 (which == 0)? XSTR(DEFAULT_CRYPT) : (which == 1)? "crypt" : "crypt16",
2640 coded, sub[1]);
2641 #undef STR
2642 #undef XSTR
2643
2644 /* If the encrypted string contains fewer than two characters (for the
2645 salt), force failure. Otherwise we get false positives: with an empty
2646 string the yield of crypt() is an empty string! */
2647
b5b871ac
JH
2648 tempcond = (Ustrlen(sub[1]) < 2)? FALSE :
2649 (Ustrcmp(coded, sub[1]) == 0);
059ec3d9
PH
2650 }
2651 break;
2652 #endif /* SUPPORT_CRYPTEQ */
76dca828
PP
2653
2654 case ECOND_INLIST:
2655 case ECOND_INLISTI:
2656 {
2657 int sep = 0;
76dca828
PP
2658 uschar *save_iterate_item = iterate_item;
2659 int (*compare)(const uschar *, const uschar *);
2660
b5b871ac 2661 tempcond = FALSE;
76dca828
PP
2662 if (cond_type == ECOND_INLISTI)
2663 compare = strcmpic;
2664 else
2665 compare = (int (*)(const uschar *, const uschar *)) strcmp;
2666
2667 while ((iterate_item = string_nextinlist(&sub[1], &sep, NULL, 0)) != NULL)
2668 if (compare(sub[0], iterate_item) == 0)
2669 {
b5b871ac 2670 tempcond = TRUE;
76dca828
PP
2671 break;
2672 }
2673 iterate_item = save_iterate_item;
76dca828
PP
2674 }
2675
059ec3d9
PH
2676 } /* Switch for comparison conditions */
2677
b5b871ac 2678 *yield = tempcond == testfor;
059ec3d9
PH
2679 return s; /* End of comparison conditions */
2680
2681
2682 /* and/or: computes logical and/or of several conditions */
2683
2684 case ECOND_AND:
2685 case ECOND_OR:
2686 subcondptr = (yield == NULL)? NULL : &tempcond;
2687 combined_cond = (cond_type == ECOND_AND);
2688
2689 while (isspace(*s)) s++;
b5b871ac 2690 if (*s++ != '{') goto COND_FAILED_CURLY_START; /* }-for-text-editors */
059ec3d9
PH
2691
2692 for (;;)
2693 {
2694 while (isspace(*s)) s++;
b5b871ac 2695 /* {-for-text-editors */
059ec3d9 2696 if (*s == '}') break;
b5b871ac 2697 if (*s != '{') /* }-for-text-editors */
059ec3d9
PH
2698 {
2699 expand_string_message = string_sprintf("each subcondition "
2700 "inside an \"%s{...}\" condition must be in its own {}", name);
2701 return NULL;
2702 }
2703
b0e85a8f 2704 if (!(s = eval_condition(s+1, resetok, subcondptr)))
059ec3d9
PH
2705 {
2706 expand_string_message = string_sprintf("%s inside \"%s{...}\" condition",
2707 expand_string_message, name);
2708 return NULL;
2709 }
2710 while (isspace(*s)) s++;
2711
b5b871ac 2712 /* {-for-text-editors */
059ec3d9
PH
2713 if (*s++ != '}')
2714 {
b5b871ac 2715 /* {-for-text-editors */
059ec3d9
PH
2716 expand_string_message = string_sprintf("missing } at end of condition "
2717 "inside \"%s\" group", name);
2718 return NULL;
2719 }
2720
2721 if (yield != NULL)
2722 {
2723 if (cond_type == ECOND_AND)
2724 {
2725 combined_cond &= tempcond;
2726 if (!combined_cond) subcondptr = NULL; /* once false, don't */
2727 } /* evaluate any more */
2728 else
2729 {
2730 combined_cond |= tempcond;
2731 if (combined_cond) subcondptr = NULL; /* once true, don't */
2732 } /* evaluate any more */
2733 }
2734 }
2735
2736 if (yield != NULL) *yield = (combined_cond == testfor);
2737 return ++s;
2738
2739
0ce9abe6
PH
2740 /* forall/forany: iterates a condition with different values */
2741
2742 case ECOND_FORALL:
2743 case ECOND_FORANY:
2744 {
2745 int sep = 0;
282b357d 2746 uschar *save_iterate_item = iterate_item;
0ce9abe6
PH
2747
2748 while (isspace(*s)) s++;
b5b871ac 2749 if (*s++ != '{') goto COND_FAILED_CURLY_START; /* }-for-text-editors */
b0e85a8f 2750 sub[0] = expand_string_internal(s, TRUE, &s, (yield == NULL), TRUE, resetok);
0ce9abe6 2751 if (sub[0] == NULL) return NULL;
b5b871ac 2752 /* {-for-text-editors */
0ce9abe6
PH
2753 if (*s++ != '}') goto COND_FAILED_CURLY_END;
2754
2755 while (isspace(*s)) s++;
b5b871ac 2756 if (*s++ != '{') goto COND_FAILED_CURLY_START; /* }-for-text-editors */
0ce9abe6
PH
2757
2758 sub[1] = s;
2759
2760 /* Call eval_condition once, with result discarded (as if scanning a
2761 "false" part). This allows us to find the end of the condition, because if
2762 the list it empty, we won't actually evaluate the condition for real. */
2763
b0e85a8f 2764 if (!(s = eval_condition(sub[1], resetok, NULL)))
0ce9abe6
PH
2765 {
2766 expand_string_message = string_sprintf("%s inside \"%s\" condition",
2767 expand_string_message, name);
2768 return NULL;
2769 }
2770 while (isspace(*s)) s++;
2771
b5b871ac 2772 /* {-for-text-editors */
0ce9abe6
PH
2773 if (*s++ != '}')
2774 {
b5b871ac 2775 /* {-for-text-editors */
0ce9abe6
PH
2776 expand_string_message = string_sprintf("missing } at end of condition "
2777 "inside \"%s\"", name);
2778 return NULL;
2779 }
2780
2781 if (yield != NULL) *yield = !testfor;
2782 while ((iterate_item = string_nextinlist(&sub[0], &sep, NULL, 0)) != NULL)
2783 {
2784 DEBUG(D_expand) debug_printf("%s: $item = \"%s\"\n", name, iterate_item);
b0e85a8f 2785 if (!eval_condition(sub[1], resetok, &tempcond))
0ce9abe6
PH
2786 {
2787 expand_string_message = string_sprintf("%s inside \"%s\" condition",
2788 expand_string_message, name);
e58c13cc 2789 iterate_item = save_iterate_item;
0ce9abe6
PH
2790 return NULL;
2791 }
2792 DEBUG(D_expand) debug_printf("%s: condition evaluated to %s\n", name,
2793 tempcond? "true":"false");
2794
2795 if (yield != NULL) *yield = (tempcond == testfor);
2796 if (tempcond == (cond_type == ECOND_FORANY)) break;
2797 }
2798
282b357d 2799 iterate_item = save_iterate_item;
0ce9abe6
PH
2800 return s;
2801 }
2802
2803
f3766eb5
NM
2804 /* The bool{} expansion condition maps a string to boolean.
2805 The values supported should match those supported by the ACL condition
2806 (acl.c, ACLC_CONDITION) so that we keep to a minimum the different ideas
2807 of true/false. Note that Router "condition" rules have a different
2808 interpretation, where general data can be used and only a few values
2809 map to FALSE.
2810 Note that readconf.c boolean matching, for boolean configuration options,
6a8de854
PP
2811 only matches true/yes/false/no.
2812 The bool_lax{} condition matches the Router logic, which is much more
2813 liberal. */
f3766eb5 2814 case ECOND_BOOL:
6a8de854 2815 case ECOND_BOOL_LAX:
f3766eb5
NM
2816 {
2817 uschar *sub_arg[1];
71265ae9 2818 uschar *t, *t2;
6a8de854 2819 uschar *ourname;
f3766eb5
NM
2820 size_t len;
2821 BOOL boolvalue = FALSE;
2822 while (isspace(*s)) s++;
b5b871ac 2823 if (*s != '{') goto COND_FAILED_CURLY_START; /* }-for-text-editors */
6a8de854 2824 ourname = cond_type == ECOND_BOOL_LAX ? US"bool_lax" : US"bool";
b0e85a8f 2825 switch(read_subs(sub_arg, 1, 1, &s, yield == NULL, FALSE, ourname, resetok))
f3766eb5 2826 {
6a8de854
PP
2827 case 1: expand_string_message = string_sprintf(
2828 "too few arguments or bracketing error for %s",
2829 ourname);
f3766eb5
NM
2830 /*FALLTHROUGH*/
2831 case 2:
2832 case 3: return NULL;
2833 }
2834 t = sub_arg[0];
2835 while (isspace(*t)) t++;
2836 len = Ustrlen(t);
71265ae9
PP
2837 if (len)
2838 {
2839 /* trailing whitespace: seems like a good idea to ignore it too */
2840 t2 = t + len - 1;
2841 while (isspace(*t2)) t2--;
2842 if (t2 != (t + len))
2843 {
2844 *++t2 = '\0';
2845 len = t2 - t;
2846 }
2847 }
f3766eb5 2848 DEBUG(D_expand)
6a8de854
PP
2849 debug_printf("considering %s: %s\n", ourname, len ? t : US"<empty>");
2850 /* logic for the lax case from expand_check_condition(), which also does
2851 expands, and the logic is both short and stable enough that there should
2852 be no maintenance burden from replicating it. */
f3766eb5
NM
2853 if (len == 0)
2854 boolvalue = FALSE;
51c7471d
JH
2855 else if (*t == '-'
2856 ? Ustrspn(t+1, "0123456789") == len-1
2857 : Ustrspn(t, "0123456789") == len)
6a8de854 2858 {
f3766eb5 2859 boolvalue = (Uatoi(t) == 0) ? FALSE : TRUE;
6a8de854
PP
2860 /* expand_check_condition only does a literal string "0" check */
2861 if ((cond_type == ECOND_BOOL_LAX) && (len > 1))
2862 boolvalue = TRUE;
2863 }
f3766eb5
NM
2864 else if (strcmpic(t, US"true") == 0 || strcmpic(t, US"yes") == 0)
2865 boolvalue = TRUE;
2866 else if (strcmpic(t, US"false") == 0 || strcmpic(t, US"no") == 0)
2867 boolvalue = FALSE;
6a8de854
PP
2868 else if (cond_type == ECOND_BOOL_LAX)
2869 boolvalue = TRUE;
f3766eb5
NM
2870 else
2871 {
2872 expand_string_message = string_sprintf("unrecognised boolean "
2873 "value \"%s\"", t);
2874 return NULL;
2875 }
5ee6f336 2876 if (yield != NULL) *yield = (boolvalue == testfor);
f3766eb5
NM
2877 return s;
2878 }
2879
059ec3d9
PH
2880 /* Unknown condition */
2881
2882 default:
2883 expand_string_message = string_sprintf("unknown condition \"%s\"", name);
2884 return NULL;
2885 } /* End switch on condition type */
2886
2887/* Missing braces at start and end of data */
2888
2889COND_FAILED_CURLY_START:
2890expand_string_message = string_sprintf("missing { after \"%s\"", name);
2891return NULL;
2892
2893COND_FAILED_CURLY_END:
2894expand_string_message = string_sprintf("missing } at end of \"%s\" condition",
2895 name);
2896return NULL;
2897
2898/* A condition requires code that is not compiled */
2899
2900#if !defined(SUPPORT_PAM) || !defined(RADIUS_CONFIG_FILE) || \
2901 !defined(LOOKUP_LDAP) || !defined(CYRUS_PWCHECK_SOCKET) || \
2902 !defined(SUPPORT_CRYPTEQ) || !defined(CYRUS_SASLAUTHD_SOCKET)
2903COND_FAILED_NOT_COMPILED:
2904expand_string_message = string_sprintf("support for \"%s\" not compiled",
2905 name);
2906return NULL;
2907#endif
2908}
2909
2910
2911
2912
2913/*************************************************
2914* Save numerical variables *
2915*************************************************/
2916
2917/* This function is called from items such as "if" that want to preserve and
2918restore the numbered variables.
2919
2920Arguments:
2921 save_expand_string points to an array of pointers to set
2922 save_expand_nlength points to an array of ints for the lengths
2923
2924Returns: the value of expand max to save
2925*/
2926
2927static int
2928save_expand_strings(uschar **save_expand_nstring, int *save_expand_nlength)
2929{
2930int i;
2931for (i = 0; i <= expand_nmax; i++)
2932 {
2933 save_expand_nstring[i] = expand_nstring[i];
2934 save_expand_nlength[i] = expand_nlength[i];
2935 }
2936return expand_nmax;
2937}
2938
2939
2940
2941/*************************************************
2942* Restore numerical variables *
2943*************************************************/
2944
2945/* This function restored saved values of numerical strings.
2946
2947Arguments:
2948 save_expand_nmax the number of strings to restore
2949 save_expand_string points to an array of pointers
2950 save_expand_nlength points to an array of ints
2951
2952Returns: nothing
2953*/
2954
2955static void
2956restore_expand_strings(int save_expand_nmax, uschar **save_expand_nstring,
2957 int *save_expand_nlength)
2958{
2959int i;
2960expand_nmax = save_expand_nmax;
2961for (i = 0; i <= expand_nmax; i++)
2962 {
2963 expand_nstring[i] = save_expand_nstring[i];
2964 expand_nlength[i] = save_expand_nlength[i];
2965 }
2966}
2967
2968
2969
2970
2971
2972/*************************************************
2973* Handle yes/no substrings *
2974*************************************************/
2975
2976/* This function is used by ${if}, ${lookup} and ${extract} to handle the
2977alternative substrings that depend on whether or not the condition was true,
2978or the lookup or extraction succeeded. The substrings always have to be
2979expanded, to check their syntax, but "skipping" is set when the result is not
2980needed - this avoids unnecessary nested lookups.
2981
2982Arguments:
2983 skipping TRUE if we were skipping when this item was reached
2984 yes TRUE if the first string is to be used, else use the second
2985 save_lookup a value to put back into lookup_value before the 2nd expansion
2986 sptr points to the input string pointer
2987 yieldptr points to the output string pointer
2988 sizeptr points to the output string size
2989 ptrptr points to the output string pointer
2990 type "lookup" or "if" or "extract" or "run", for error message
b0e85a8f
JH
2991 resetok if not NULL, pointer to flag - write FALSE if unsafe to reset
2992 the store.
059ec3d9
PH
2993
2994Returns: 0 OK; lookup_value has been reset to save_lookup
2995 1 expansion failed
2996 2 expansion failed because of bracketing error
2997*/
2998
2999static int
3000process_yesno(BOOL skipping, BOOL yes, uschar *save_lookup, uschar **sptr,
b0e85a8f 3001 uschar **yieldptr, int *sizeptr, int *ptrptr, uschar *type, BOOL *resetok)
059ec3d9
PH
3002{
3003int rc = 0;
3004uschar *s = *sptr; /* Local value */
3005uschar *sub1, *sub2;
3006
3007/* If there are no following strings, we substitute the contents of $value for
063b1e99 3008lookups and for extractions in the success case. For the ${if item, the string
8e669ac1 3009"true" is substituted. In the fail case, nothing is substituted for all three
063b1e99 3010items. */
059ec3d9
PH
3011
3012while (isspace(*s)) s++;
3013if (*s == '}')
3014 {
063b1e99
PH
3015 if (type[0] == 'i')
3016 {
8e669ac1 3017 if (yes) *yieldptr = string_cat(*yieldptr, sizeptr, ptrptr, US"true", 4);
063b1e99
PH
3018 }
3019 else
8e669ac1 3020 {
063b1e99
PH
3021 if (yes && lookup_value != NULL)
3022 *yieldptr = string_cat(*yieldptr, sizeptr, ptrptr, lookup_value,
3023 Ustrlen(lookup_value));
3024 lookup_value = save_lookup;
3025 }
059ec3d9
PH
3026 s++;
3027 goto RETURN;
3028 }
3029
9b4768fa
PH
3030/* The first following string must be braced. */
3031
3032if (*s++ != '{') goto FAILED_CURLY;
3033
059ec3d9
PH
3034/* Expand the first substring. Forced failures are noticed only if we actually
3035want this string. Set skipping in the call in the fail case (this will always
3036be the case if we were already skipping). */
3037
b0e85a8f 3038sub1 = expand_string_internal(s, TRUE, &s, !yes, TRUE, resetok);
059ec3d9
PH
3039if (sub1 == NULL && (yes || !expand_string_forcedfail)) goto FAILED;
3040expand_string_forcedfail = FALSE;
3041if (*s++ != '}') goto FAILED_CURLY;
3042
3043/* If we want the first string, add it to the output */
3044
3045if (yes)
3046 *yieldptr = string_cat(*yieldptr, sizeptr, ptrptr, sub1, Ustrlen(sub1));
3047
3048/* If this is called from a lookup or an extract, we want to restore $value to
3049what it was at the start of the item, so that it has this value during the
d20976dc
PH
3050second string expansion. For the call from "if" or "run" to this function,
3051save_lookup is set to lookup_value, so that this statement does nothing. */
059ec3d9
PH
3052
3053lookup_value = save_lookup;
3054
3055/* There now follows either another substring, or "fail", or nothing. This
3056time, forced failures are noticed only if we want the second string. We must
3057set skipping in the nested call if we don't want this string, or if we were
3058already skipping. */
3059
3060while (isspace(*s)) s++;
3061if (*s == '{')
3062 {
b0e85a8f 3063 sub2 = expand_string_internal(s+1, TRUE, &s, yes || skipping, TRUE, resetok);
059ec3d9
PH
3064 if (sub2 == NULL && (!yes || !expand_string_forcedfail)) goto FAILED;
3065 expand_string_forcedfail = FALSE;
3066 if (*s++ != '}') goto FAILED_CURLY;
3067
3068 /* If we want the second string, add it to the output */
3069
3070 if (!yes)
3071 *yieldptr = string_cat(*yieldptr, sizeptr, ptrptr, sub2, Ustrlen(sub2));
3072 }
3073
3074/* If there is no second string, but the word "fail" is present when the use of
3075the second string is wanted, set a flag indicating it was a forced failure
3076rather than a syntactic error. Swallow the terminating } in case this is nested
3077inside another lookup or if or extract. */
3078
3079else if (*s != '}')
3080 {
3081 uschar name[256];
3082 s = read_name(name, sizeof(name), s, US"_");
3083 if (Ustrcmp(name, "fail") == 0)
3084 {
3085 if (!yes && !skipping)
3086 {
3087 while (isspace(*s)) s++;
3088 if (*s++ != '}') goto FAILED_CURLY;
3089 expand_string_message =
3090 string_sprintf("\"%s\" failed and \"fail\" requested", type);
3091 expand_string_forcedfail = TRUE;
3092 goto FAILED;
3093 }
3094 }
3095 else
3096 {
3097 expand_string_message =
3098 string_sprintf("syntax error in \"%s\" item - \"fail\" expected", type);
3099 goto FAILED;
3100 }
3101 }
3102
3103/* All we have to do now is to check on the final closing brace. */
3104
3105while (isspace(*s)) s++;
3106if (*s++ == '}') goto RETURN;
3107
3108/* Get here if there is a bracketing failure */
3109
3110FAILED_CURLY:
3111rc++;
3112
3113/* Get here for other failures */
3114
3115FAILED:
3116rc++;
3117
3118/* Update the input pointer value before returning */
3119
3120RETURN:
3121*sptr = s;
3122return rc;
3123}
3124
3125
3126
3127
059ec3d9
PH
3128/*************************************************
3129* Handle MD5 or SHA-1 computation for HMAC *
3130*************************************************/
3131
3132/* These are some wrapping functions that enable the HMAC code to be a bit
3133cleaner. A good compiler will spot the tail recursion.
3134
3135Arguments:
3136 type HMAC_MD5 or HMAC_SHA1
3137 remaining are as for the cryptographic hash functions
3138
3139Returns: nothing
3140*/
3141
3142static void
3143chash_start(int type, void *base)
3144{
3145if (type == HMAC_MD5)
3146 md5_start((md5 *)base);
3147else
3148 sha1_start((sha1 *)base);
3149}
3150
3151static void
3152chash_mid(int type, void *base, uschar *string)
3153{
3154if (type == HMAC_MD5)
3155 md5_mid((md5 *)base, string);
3156else
3157 sha1_mid((sha1 *)base, string);
3158}
3159
3160static void
3161chash_end(int type, void *base, uschar *string, int length, uschar *digest)
3162{
3163if (type == HMAC_MD5)
3164 md5_end((md5 *)base, string, length, digest);
3165else
3166 sha1_end((sha1 *)base, string, length, digest);
3167}
3168
3169
3170
3171
3172
1549ea3b
PH
3173/********************************************************
3174* prvs: Get last three digits of days since Jan 1, 1970 *
3175********************************************************/
3176
3177/* This is needed to implement the "prvs" BATV reverse
3178 path signing scheme
3179
3180Argument: integer "days" offset to add or substract to
3181 or from the current number of days.
3182
3183Returns: pointer to string containing the last three
3184 digits of the number of days since Jan 1, 1970,
3185 modified by the offset argument, NULL if there
3186 was an error in the conversion.
3187
3188*/
3189
3190static uschar *
3191prvs_daystamp(int day_offset)
3192{
a86229cf
PH
3193uschar *days = store_get(32); /* Need at least 24 for cases */
3194(void)string_format(days, 32, TIME_T_FMT, /* where TIME_T_FMT is %lld */
1549ea3b 3195 (time(NULL) + day_offset*86400)/86400);
e169f567 3196return (Ustrlen(days) >= 3) ? &days[Ustrlen(days)-3] : US"100";
1549ea3b
PH
3197}
3198
3199
3200
3201/********************************************************
3202* prvs: perform HMAC-SHA1 computation of prvs bits *
3203********************************************************/
3204
3205/* This is needed to implement the "prvs" BATV reverse
3206 path signing scheme
3207
3208Arguments:
3209 address RFC2821 Address to use
3210 key The key to use (must be less than 64 characters
3211 in size)
3212 key_num Single-digit key number to use. Defaults to
3213 '0' when NULL.
3214
3215Returns: pointer to string containing the first three
3216 bytes of the final hash in hex format, NULL if
3217 there was an error in the process.
3218*/
3219
3220static uschar *
3221prvs_hmac_sha1(uschar *address, uschar *key, uschar *key_num, uschar *daystamp)
3222{
3223uschar *hash_source, *p;
3224int size = 0,offset = 0,i;
3225sha1 sha1_base;
3226void *use_base = &sha1_base;
3227uschar innerhash[20];
3228uschar finalhash[20];
3229uschar innerkey[64];
3230uschar outerkey[64];
3231uschar *finalhash_hex = store_get(40);
3232
3233if (key_num == NULL)
3234 key_num = US"0";
3235
3236if (Ustrlen(key) > 64)
3237 return NULL;
3238
3239hash_source = string_cat(NULL,&size,&offset,key_num,1);
3240string_cat(hash_source,&size,&offset,daystamp,3);
3241string_cat(hash_source,&size,&offset,address,Ustrlen(address));
3242hash_source[offset] = '\0';
3243
3244DEBUG(D_expand) debug_printf("prvs: hash source is '%s'\n", hash_source);
3245
3246memset(innerkey, 0x36, 64);
3247memset(outerkey, 0x5c, 64);
3248
3249for (i = 0; i < Ustrlen(key); i++)
3250 {
3251 innerkey[i] ^= key[i];
3252 outerkey[i] ^= key[i];
3253 }
3254
3255chash_start(HMAC_SHA1, use_base);
3256chash_mid(HMAC_SHA1, use_base, innerkey);
3257chash_end(HMAC_SHA1, use_base, hash_source, offset, innerhash);
3258
3259chash_start(HMAC_SHA1, use_base);
3260chash_mid(HMAC_SHA1, use_base, outerkey);
3261chash_end(HMAC_SHA1, use_base, innerhash, 20, finalhash);
3262
3263p = finalhash_hex;
3264for (i = 0; i < 3; i++)
3265 {
3266 *p++ = hex_digits[(finalhash[i] & 0xf0) >> 4];
3267 *p++ = hex_digits[finalhash[i] & 0x0f];
3268 }
3269*p = '\0';
3270
3271return finalhash_hex;
3272}
3273
3274
3275
3276
059ec3d9
PH
3277/*************************************************
3278* Join a file onto the output string *
3279*************************************************/
3280
3281/* This is used for readfile and after a run expansion. It joins the contents
3282of a file onto the output string, globally replacing newlines with a given
3283string (optionally). The file is closed at the end.
3284
3285Arguments:
3286 f the FILE
3287 yield pointer to the expandable string
3288 sizep pointer to the current size
3289 ptrp pointer to the current position
3290 eol newline replacement string, or NULL
3291
3292Returns: new value of string pointer
3293*/
3294
3295static uschar *
3296cat_file(FILE *f, uschar *yield, int *sizep, int *ptrp, uschar *eol)
3297{
3298int eollen;
3299uschar buffer[1024];
3300
3301eollen = (eol == NULL)? 0 : Ustrlen(eol);
3302
3303while (Ufgets(buffer, sizeof(buffer), f) != NULL)
3304 {
3305 int len = Ustrlen(buffer);
3306 if (eol != NULL && buffer[len-1] == '\n') len--;
3307 yield = string_cat(yield, sizep, ptrp, buffer, len);
3308 if (buffer[len] != 0)
3309 yield = string_cat(yield, sizep, ptrp, eol, eollen);
3310 }
3311
3312if (yield != NULL) yield[*ptrp] = 0;
3313
3314return yield;
3315}
3316
3317
3318
3319
3320/*************************************************
3321* Evaluate numeric expression *
3322*************************************************/
3323
af561417
PH
3324/* This is a set of mutually recursive functions that evaluate an arithmetic
3325expression involving + - * / % & | ^ ~ << >> and parentheses. The only one of
3326these functions that is called from elsewhere is eval_expr, whose interface is:
059ec3d9
PH
3327
3328Arguments:
af561417
PH
3329 sptr pointer to the pointer to the string - gets updated
3330 decimal TRUE if numbers are to be assumed decimal
3331 error pointer to where to put an error message - must be NULL on input
3332 endket TRUE if ')' must terminate - FALSE for external call
059ec3d9 3333
af561417
PH
3334Returns: on success: the value of the expression, with *error still NULL
3335 on failure: an undefined value, with *error = a message
059ec3d9
PH
3336*/
3337
97d17305 3338static int_eximarith_t eval_op_or(uschar **, BOOL, uschar **);
af561417 3339
059ec3d9 3340
97d17305 3341static int_eximarith_t
059ec3d9
PH
3342eval_expr(uschar **sptr, BOOL decimal, uschar **error, BOOL endket)
3343{
3344uschar *s = *sptr;
97d17305 3345int_eximarith_t x = eval_op_or(&s, decimal, error);
059ec3d9
PH
3346if (*error == NULL)
3347 {
af561417 3348 if (endket)
059ec3d9 3349 {
af561417
PH
3350 if (*s != ')')
3351 *error = US"expecting closing parenthesis";
3352 else
3353 while (isspace(*(++s)));
059ec3d9 3354 }
af561417 3355 else if (*s != 0) *error = US"expecting operator";
059ec3d9 3356 }
059ec3d9
PH
3357*sptr = s;
3358return x;
3359}
3360
af561417 3361
97d17305 3362static int_eximarith_t
af561417 3363eval_number(uschar **sptr, BOOL decimal, uschar **error)
059ec3d9
PH
3364{
3365register int c;
97d17305 3366int_eximarith_t n;
059ec3d9
PH
3367uschar *s = *sptr;
3368while (isspace(*s)) s++;
3369c = *s;
af561417 3370if (isdigit(c))
059ec3d9
PH
3371 {
3372 int count;
97d17305 3373 (void)sscanf(CS s, (decimal? SC_EXIM_DEC "%n" : SC_EXIM_ARITH "%n"), &n, &count);
059ec3d9 3374 s += count;
97d17305
JH
3375 switch (tolower(*s))
3376 {
3377 default: break;
3378 case 'k': n *= 1024; s++; break;
3379 case 'm': n *= 1024*1024; s++; break;
3380 case 'g': n *= 1024*1024*1024; s++; break;
3381 }
059ec3d9
PH
3382 while (isspace (*s)) s++;
3383 }
3384else if (c == '(')
3385 {
3386 s++;
3387 n = eval_expr(&s, decimal, error, 1);
3388 }
3389else
3390 {
3391 *error = US"expecting number or opening parenthesis";
3392 n = 0;
3393 }
3394*sptr = s;
3395return n;
3396}
3397
af561417 3398
97d17305 3399static int_eximarith_t
aa7c82b2 3400eval_op_unary(uschar **sptr, BOOL decimal, uschar **error)
af561417
PH
3401{
3402uschar *s = *sptr;
97d17305 3403int_eximarith_t x;
af561417
PH
3404while (isspace(*s)) s++;
3405if (*s == '+' || *s == '-' || *s == '~')
3406 {
3407 int op = *s++;
3408 x = eval_op_unary(&s, decimal, error);
3409 if (op == '-') x = -x;
3410 else if (op == '~') x = ~x;
3411 }
3412else
3413 {
3414 x = eval_number(&s, decimal, error);
3415 }
3416*sptr = s;
3417return x;
3418}
3419
3420
97d17305 3421static int_eximarith_t
aa7c82b2 3422eval_op_mult(uschar **sptr, BOOL decimal, uschar **error)
059ec3d9
PH
3423{
3424uschar *s = *sptr;
97d17305 3425int_eximarith_t x = eval_op_unary(&s, decimal, error);
059ec3d9
PH
3426if (*error == NULL)
3427 {
5591031b 3428 while (*s == '*' || *s == '/' || *s == '%')
059ec3d9
PH
3429 {
3430 int op = *s++;
97d17305 3431 int_eximarith_t y = eval_op_unary(&s, decimal, error);
059ec3d9 3432 if (*error != NULL) break;
053a9aa3
PP
3433 /* SIGFPE both on div/mod by zero and on INT_MIN / -1, which would give
3434 * a value of INT_MAX+1. Note that INT_MIN * -1 gives INT_MIN for me, which
3435 * is a bug somewhere in [gcc 4.2.1, FreeBSD, amd64]. In fact, -N*-M where
3436 * -N*M is INT_MIN will yielf INT_MIN.
3437 * Since we don't support floating point, this is somewhat simpler.
3438 * Ideally, we'd return an error, but since we overflow for all other
3439 * arithmetic, consistency suggests otherwise, but what's the correct value
3440 * to use? There is none.
3441 * The C standard guarantees overflow for unsigned arithmetic but signed
3442 * overflow invokes undefined behaviour; in practice, this is overflow
3443 * except for converting INT_MIN to INT_MAX+1. We also can't guarantee
3444 * that long/longlong larger than int are available, or we could just work
3445 * with larger types. We should consider whether to guarantee 32bit eval
3446 * and 64-bit working variables, with errors returned. For now ...
3447 * So, the only SIGFPEs occur with a non-shrinking div/mod, thus -1; we
3448 * can just let the other invalid results occur otherwise, as they have
3449 * until now. For this one case, we can coerce.
3450 */
4328fd3c 3451 if (y == -1 && x == EXIM_ARITH_MIN && op != '*')
053a9aa3
PP
3452 {
3453 DEBUG(D_expand)
97d17305 3454 debug_printf("Integer exception dodging: " PR_EXIM_ARITH "%c-1 coerced to " PR_EXIM_ARITH "\n",
4328fd3c
JH
3455 EXIM_ARITH_MIN, op, EXIM_ARITH_MAX);
3456 x = EXIM_ARITH_MAX;
053a9aa3
PP
3457 continue;
3458 }
a5b52695
PP
3459 if (op == '*')
3460 x *= y;
3461 else
3462 {
3463 if (y == 0)
54e7ce4a 3464 {
a5b52695
PP
3465 *error = (op == '/') ? US"divide by zero" : US"modulo by zero";
3466 x = 0;
3467 break;
54e7ce4a 3468 }
a5b52695
PP
3469 if (op == '/')
3470 x /= y;
3471 else
3472 x %= y;
3473 }
059ec3d9
PH
3474 }
3475 }
3476*sptr = s;
3477return x;
3478}
3479
3480
97d17305 3481static int_eximarith_t
aa7c82b2 3482eval_op_sum(uschar **sptr, BOOL decimal, uschar **error)
af561417
PH
3483{
3484uschar *s = *sptr;
97d17305 3485int_eximarith_t x = eval_op_mult(&s, decimal, error);
af561417
PH
3486if (*error == NULL)
3487 {
3488 while (*s == '+' || *s == '-')
3489 {
3490 int op = *s++;
97d17305 3491 int_eximarith_t y = eval_op_mult(&s, decimal, error);
af561417
PH
3492 if (*error != NULL) break;
3493 if (op == '+') x += y; else x -= y;
3494 }
3495 }
3496*sptr = s;
3497return x;
3498}
3499
3500
97d17305 3501static int_eximarith_t
aa7c82b2 3502eval_op_shift(uschar **sptr, BOOL decimal, uschar **error)
af561417
PH
3503{
3504uschar *s = *sptr;
97d17305 3505int_eximarith_t x = eval_op_sum(&s, decimal, error);
af561417
PH
3506if (*error == NULL)
3507 {
3508 while ((*s == '<' || *s == '>') && s[1] == s[0])
3509 {
97d17305 3510 int_eximarith_t y;
af561417
PH
3511 int op = *s++;
3512 s++;
3513 y = eval_op_sum(&s, decimal, error);
3514 if (*error != NULL) break;
3515 if (op == '<') x <<= y; else x >>= y;
3516 }
3517 }
3518*sptr = s;
3519return x;
3520}
3521
3522
97d17305 3523static int_eximarith_t
aa7c82b2 3524eval_op_and(uschar **sptr, BOOL decimal, uschar **error)
af561417
PH
3525{
3526uschar *s = *sptr;
97d17305 3527int_eximarith_t x = eval_op_shift(&s, decimal, error);
af561417
PH
3528if (*error == NULL)
3529 {
3530 while (*s == '&')
3531 {
97d17305 3532 int_eximarith_t y;
af561417
PH
3533 s++;
3534 y = eval_op_shift(&s, decimal, error);
3535 if (*error != NULL) break;
3536 x &= y;
3537 }
3538 }
3539*sptr = s;
3540return x;
3541}
3542
3543
97d17305 3544static int_eximarith_t
aa7c82b2 3545eval_op_xor(uschar **sptr, BOOL decimal, uschar **error)
af561417
PH
3546{
3547uschar *s = *sptr;
97d17305 3548int_eximarith_t x = eval_op_and(&s, decimal, error);
af561417
PH
3549if (*error == NULL)
3550 {
3551 while (*s == '^')
3552 {
97d17305 3553 int_eximarith_t y;
af561417
PH
3554 s++;
3555 y = eval_op_and(&s, decimal, error);
3556 if (*error != NULL) break;
3557 x ^= y;
3558 }
3559 }
3560*sptr = s;
3561return x;
3562}
3563
3564
97d17305 3565static int_eximarith_t
aa7c82b2 3566eval_op_or(uschar **sptr, BOOL decimal, uschar **error)
af561417
PH
3567{
3568uschar *s = *sptr;
97d17305 3569int_eximarith_t x = eval_op_xor(&s, decimal, error);
af561417
PH
3570if (*error == NULL)
3571 {
3572 while (*s == '|')
3573 {
97d17305 3574 int_eximarith_t y;
af561417
PH
3575 s++;
3576 y = eval_op_xor(&s, decimal, error);
3577 if (*error != NULL) break;
3578 x |= y;
3579 }
3580 }
3581*sptr = s;
3582return x;
3583}
3584
059ec3d9
PH
3585
3586
3587/*************************************************
3588* Expand string *
3589*************************************************/
3590
3591/* Returns either an unchanged string, or the expanded string in stacking pool
3592store. Interpreted sequences are:
3593
3594 \... normal escaping rules
3595 $name substitutes the variable
3596 ${name} ditto
3597 ${op:string} operates on the expanded string value
3598 ${item{arg1}{arg2}...} expands the args and then does the business
3599 some literal args are not enclosed in {}
3600
3601There are now far too many operators and item types to make it worth listing
3602them here in detail any more.
3603
3604We use an internal routine recursively to handle embedded substrings. The
3605external function follows. The yield is NULL if the expansion failed, and there
3606are two cases: if something collapsed syntactically, or if "fail" was given
3607as the action on a lookup failure. These can be distinguised by looking at the
3608variable expand_string_forcedfail, which is TRUE in the latter case.
3609
3610The skipping flag is set true when expanding a substring that isn't actually
3611going to be used (after "if" or "lookup") and it prevents lookups from
3612happening lower down.
3613
3614Store usage: At start, a store block of the length of the input plus 64
3615is obtained. This is expanded as necessary by string_cat(), which might have to
3616get a new block, or might be able to expand the original. At the end of the
3617function we can release any store above that portion of the yield block that
3618was actually used. In many cases this will be optimal.
3619
3620However: if the first item in the expansion is a variable name or header name,
3621we reset the store before processing it; if the result is in fresh store, we
3622use that without copying. This is helpful for expanding strings like
3623$message_headers which can get very long.
3624
d6b4d938
TF
3625There's a problem if a ${dlfunc item has side-effects that cause allocation,
3626since resetting the store at the end of the expansion will free store that was
3627allocated by the plugin code as well as the slop after the expanded string. So
b0e85a8f
JH
3628we skip any resets if ${dlfunc } has been used. The same applies for ${acl }
3629and, given the acl condition, ${if }. This is an unfortunate consequence of
3630string expansion becoming too powerful.
d6b4d938 3631
059ec3d9
PH
3632Arguments:
3633 string the string to be expanded
3634 ket_ends true if expansion is to stop at }
3635 left if not NULL, a pointer to the first character after the
3636 expansion is placed here (typically used with ket_ends)
3637 skipping TRUE for recursive calls when the value isn't actually going
3638 to be used (to allow for optimisation)
da6dbe26
PP
3639 honour_dollar TRUE if $ is to be expanded,
3640 FALSE if it's just another character
b0e85a8f
JH
3641 resetok_p if not NULL, pointer to flag - write FALSE if unsafe to reset
3642 the store.
059ec3d9
PH
3643
3644Returns: NULL if expansion fails:
3645 expand_string_forcedfail is set TRUE if failure was forced
3646 expand_string_message contains a textual error message
3647 a pointer to the expanded string on success
3648*/
3649
3650static uschar *
3651expand_string_internal(uschar *string, BOOL ket_ends, uschar **left,
b0e85a8f 3652 BOOL skipping, BOOL honour_dollar, BOOL *resetok_p)
059ec3d9
PH
3653{
3654int ptr = 0;
3655int size = Ustrlen(string)+ 64;
3656int item_type;
3657uschar *yield = store_get(size);
3658uschar *s = string;
3659uschar *save_expand_nstring[EXPAND_MAXN+1];
3660int save_expand_nlength[EXPAND_MAXN+1];
d6b4d938 3661BOOL resetok = TRUE;
059ec3d9
PH
3662
3663expand_string_forcedfail = FALSE;
3664expand_string_message = US"";
3665
3666while (*s != 0)
3667 {
3668 uschar *value;
3669 uschar name[256];
3670
3671 /* \ escapes the next character, which must exist, or else
3672 the expansion fails. There's a special escape, \N, which causes
3673 copying of the subject verbatim up to the next \N. Otherwise,
3674 the escapes are the standard set. */
3675
3676 if (*s == '\\')
3677 {
3678 if (s[1] == 0)
3679 {
3680 expand_string_message = US"\\ at end of string";
3681 goto EXPAND_FAILED;
3682 }
3683
3684 if (s[1] == 'N')
3685 {
3686 uschar *t = s + 2;
3687 for (s = t; *s != 0; s++) if (*s == '\\' && s[1] == 'N') break;
3688 yield = string_cat(yield, &size, &ptr, t, s - t);
3689 if (*s != 0) s += 2;
3690 }
3691
3692 else
3693 {
3694 uschar ch[1];
3695 ch[0] = string_interpret_escape(&s);
3696 s++;
3697 yield = string_cat(yield, &size, &ptr, ch, 1);
3698 }
3699
3700 continue;
3701 }
3702
2e23003a 3703 /*{*/
059ec3d9
PH
3704 /* Anything other than $ is just copied verbatim, unless we are
3705 looking for a terminating } character. */
3706
2e23003a 3707 /*{*/
059ec3d9
PH
3708 if (ket_ends && *s == '}') break;
3709
da6dbe26 3710 if (*s != '$' || !honour_dollar)
059ec3d9
PH
3711 {
3712 yield = string_cat(yield, &size, &ptr, s++, 1);
3713 continue;
3714 }
3715
3716 /* No { after the $ - must be a plain name or a number for string
3717 match variable. There has to be a fudge for variables that are the
3718 names of header fields preceded by "$header_" because header field
3719 names can contain any printing characters except space and colon.
3720 For those that don't like typing this much, "$h_" is a synonym for
3721 "$header_". A non-existent header yields a NULL value; nothing is
2e23003a 3722 inserted. */ /*}*/
059ec3d9
PH
3723
3724 if (isalpha((*(++s))))
3725 {
3726 int len;
3727 int newsize = 0;
3728
3729 s = read_name(name, sizeof(name), s, US"_");
3730
3731 /* If this is the first thing to be expanded, release the pre-allocated
3732 buffer. */
3733
3734 if (ptr == 0 && yield != NULL)
3735 {
d6b4d938 3736 if (resetok) store_reset(yield);
059ec3d9
PH
3737 yield = NULL;
3738 size = 0;
3739 }